She stood in the doorway in flannel pajamas, a toddler on her hip and two small girls clinging to her leg. Her son, about six, stood behind her. Audrey stepped aside to let me pass, but her movements were stiff, and she avoided looking directly at me. We'd spent little time together since she'd married.

I moved into the house, stopping abruptly in the entryway when I saw a three-foot hole in the linoleum that plunged to the basement. I walked past the hole and into the kitchen, which was filled with the scent of our mother's oils -- birch, eucalyptus, ravensara.

The day before I returned to England, I drove seven miles along the mountain range, then turned onto a narrow dirt road and stopped in front of a powder-blue house. I parked behind an RV that was nearly as large as the house itself. I knocked; my sister answered.

The conversation was slow, halting. Audrey asked me no questions about England or Cambridge. She had no frame of reference for my life, so we talked about hers -- how the public school system was corrupt so she was teaching her children herself, at home. Like me, Audrey had never attended a public school. When she was seventeen, she had made a fleeting effort to get her GED. She had even enlisted the help of our cousin Missy, who had come up from Salt Lake City to tutor her. Missy had worked with Audrey for an entire summer, at the end of which she'd declared that Audrey's education hovered somewhere between the fourth- and fifth-grade levels, and that a GED was out of the question. I chewed my lip and stared at her daughter, who had brought me a drawing, wondering what education she could hope to receive from a mother who had none herself.

I don't know why I said it; I suppose Shawn was on my mind. I regretted the words even as they left my lips, hated myself for saying them. I turned to pass the tea set to my sister, so she could administer justice however she saw fit, but when I saw her expression I nearly dropped it. Her mouth hung open in a perfect circle.

I had brought a small porcelain tea set for her children, and when they began to quarrel over the teapot, I gathered up the pieces. The oldest girl reminded me that she was five now, which she said was too old to have a toy taken away. "If you act like a child," I said, "I'll treat you like one."

We made breakfast for the children, then played with them in the snow. We baked, we watched crime dramas and designed beaded bracelets. It was as if I had stepped through a mirror and was living a day in the life I might have had, if I'd stayed on the mountain. But I hadn't stayed. My life had diverged from my sister's, and it felt as though there was no common ground between us. The hours passed; it was late afternoon; and still she felt distant from me, still she refused to meet my gaze.

That moment would stay with me. I would remember it the next day, when I boarded a plane in Salt Lake City, and it would still be on my mind when I landed in London. It was the shock of it that I couldn't shake. Somehow, it had never occurred to me that my sister might have lived my life before I did.

In April I began to do well. I wrote an essay on John Stuart Mill's concept of self-sovereignty, and my supervisor, Dr. David Runciman, said that if my dissertation was of the same quality, I might be accepted to Cambridge for a PhD. I was stunned: I, who had sneaked into this grand place as an impostor, might now enter through the front door. I set to work on my dissertation, again choosing Mill as the topic.

That term, I presented myself to the university like resin to a sculptor. I believed I could be remade, my mind recast. I forced myself to befriend other students, clumsily introducing myself again and again until I had a small circle of friends. Then I set out to obliterate the barriers that separated me from them. I tasted red wine for the first time, and my new friends laughed at my pinched face. I discarded my high-necked blouses and began to wear more fashionable cuts -- fitted, often sleeveless, with less restrictive necklines. In photos from this period I'm struck by the symmetry: I look like everyone else.

"Shawn used to say that," she said, fixing her eyes on mine.

We handed in our final essays for the term, then boarded a plane. On our first evening in Rome, we climbed one of the seven hills and looked out over the metropolis. Byzantine domes hovered over the city like rising balloons. It was nearly dusk; the streets were bathed in amber. It wasn't the color of a modern city, of steel, glass and concrete. It was the color of sunset. It didn't look real. Nic asked me what I thought of his home, and that was all I could say: it didn't look real.

One afternoon near the end of term, when I was eating lunch in the library cafeteria, I recognized a group of students from my program. They were seated together at a small table. I asked if I could join them, and a tall Italian named Nic nodded. From the conversation I gathered that Nic had invited the others to visit him in Rome during the spring holiday. "You can come, too," he said.

At breakfast the next morning, the others talked about their families. Someone's father was a diplomat; another's was an Oxford don. I was asked about my parents. I said my father owned a junkyard.

Nic took us to the conservatory where he'd studied violin. It was in the heart of Rome and was richly furnished, with a grand staircase and resonant halls. I tried to imagine what it would have been like to study in such a place, to walk across marble floors each morning and, day after day, come to associate learning with beauty. But my imagination failed me. I could only imagine the school as I was experiencing it now, as a kind of museum, a relic from someone else's life.

For two days we explored Rome, a city that is both a living organism and a fossil. Bleached structures from antiquity lay like dried bones, embedded in pulsating cables and thrumming traffic, the arteries of modern life. We visited the Pantheon, the Roman Forum, the Sistine Chapel. My instinct was to worship, to venerate. That was how I felt toward the whole city: that it should be behind glass, adored from a distance, never touched, never altered. My companions moved through the city differently, aware of its significance but not subdued by it. They were not hushed by the Trevi Fountain; they were not silenced by the Colosseum. Instead, as we moved from one relic to the next, they debated philosophy -- Hobbes and Descartes, Aquinas and Machiavelli. There was a kind of symbiosis in their relationship to these grand places: they gave life to the ancient architecture by making it the backdrop of their discourse, by refusing to worship at its altar as if it were a dead thing.

For the rest of the week, I experienced Rome as they did: as a place of history, but also as a place of life, of food and traffic and conflict and thunder. The city was no longer a museum; it was as vivid to me as Buck's Peak. The Piazza del Popolo. The Baths of Caracalla. Castel Sant'Angelo. These became as real to my mind as the Princess, the red railway car, the Shear. The world they represented, of philosophy, science, literature -- an entire civilization -- took on a life that was distinct from the life I had known. At the Galleria Nazionale d'Arte Antica, I stood before Caravaggio's Judith Beheading Holofernes and did not once think about chickens.

On the third night there was a rainstorm. I stood on Nic's balcony and watched streaks of lightning race across the sky, claps of thunder chasing them. It was like being on Buck's Peak, to feel such power in the earth and sky.

The next morning was cloudless. We took a picnic of wine and pastries to the grounds of the Villa Borghese. The sun was hot, the pastries ambrosial. I could not remember ever feeling more present. Someone said something about Hobbes, and without thinking I recited a line from Mill. It seemed the natural thing, to bring this voice from the past into a moment so saturated with the past already, even if the voice was mixed with my own. There was a pause while everyone checked to see who had spoken, then someone asked which text the line was from, and the conversation moved forward.

I was still breathing in the fustiness of ancient stone when I arrived in Cambridge. I rushed up the staircase, anxious to check my email, knowing there would be a message from Drew. When I opened my laptop, I saw that Drew had written, but so had someone else: my sister.

I don't know what caused the transformation, why suddenly I could engage with the great thinkers of the past, rather than revere them to the point of muteness. But there was something about that city, with its white marble and black asphalt, crusted with history, ablaze in traffic lights, that showed me I could admire the past without being silenced by it.

Audrey said she should have stopped Shawn many years ago, before he could do to me what he'd done to her. She said that when she was young, she'd wanted to tell Mother, to ask for help, but she'd thought Mother wouldn't believe her. She'd been right. Before her wedding, she'd experienced nightmares and flashbacks, and she'd told Mother about them. Mother had said the memories were false, impossible. I should have helped you, Audrey wrote. But when my own mother didn't believe me, I stopped believing myself.

I opened Audrey's message. It was written in one long paragraph, with little punctuation and many spelling errors, and at first I fixated on these grammatical irregularities as a way to mute the text. But the words would not be hushed; they shouted at me from the screen.

It was a mistake she was going to correct. I believe God will hold me accountable if I don't stop Shawn from hurting anyone else, she wrote. She was going to confront him, and our parents, and she was asking me to stand with her. I am doing this with or without you. But without you, I will probably lose.

I sat in the dark for a long time. I resented her for writing me. I felt she had torn me from one world, one life, where I was happy, and dragged me back into another.

I typed a response. I told her she was right, that of course we should stop Shawn, but I asked her to do nothing until I could return to Idaho. I don't know why I asked her to wait, what benefit I thought time would yield. I don't know what I thought would happen when we talked to our parents, but I understood instinctively what was at stake. As long as we had never asked, it was possible to believe that they would help. To tell them was to risk the unthinkable: it was to risk learning that they already knew.

Audrey did not wait, not even a day. The next morning she showed my email to Mother. I cannot imagine the details of that conversation, but I know that for Audrey it must have been a tremendous relief, laying my words before our mother, finally able to say, I'm not crazy. It happened to Tara, too.

It is painful to face reality, she wrote. To realize there was something ugly, and I refused to see it.

Don't blame yourself, I told her. Your mind was never the same after the accident.

For all of that day, Mother pondered it. Then she decided she had to hear the words from me. It was late afternoon in Idaho, nearly midnight in England, when my mother, unsure how to place an international call, found me online. The words on the screen were small, confined to a tiny text box in the corner of the browser, but somehow they seemed to swallow the room. She told me she had read my letter. I braced myself for her rage.

I had to read those lines a number of times before I understood them. Before I realized that she was not angry, not blaming me, or trying to convince me I had only imagined. She believed me.

Maybe, she said. But sometimes I think we choose our illnesses, because they benefit us in some way.

Shawn always said you picked the fights, and I guess I wanted to believe that, because it was easier. Because you were strong and rational, and anyone could see that Shawn was not.

I asked Mother why she'd never stopped Shawn from hurting me.

That didn't make sense. If I had seemed rational, why had Mother believed Shawn when he'd told her I was picking fights? That I needed to be subdued, disciplined.

Because you were so bullied by Dad, I said. You were not powerful in the house. Dad ran things, and he was not going to help us.

I'm a mother, she said. Mothers protect. And Shawn was so damaged.

I had never heard Mother admit that Dad might be mentally ill. Years before, I had told her what I'd learned in my psychology class about bipolar disorder and schizophrenia, but she had shrugged it off. Hearing her say it now felt liberating. The illness gave me something to attack besides my father, so when Mother asked why I hadn't come to her sooner, why I hadn't asked for help, I answered honestly.

I am stronger now, she said. I no longer run scared.

He will, she wrote. But it's hard for him. It reminds him of the damage his bipolar has caused to our family.

I wanted to say that she was also my mother but I didn't. I don't think Dad will believe any of this, I typed.

When I read this, I imagined my mother as a young woman, brilliant and energetic, but also anxious and complying. Then the image changed, her body thinning, elongating, her hair flowing, long and silver.

She is you, I said.

She is, Mother said. Like I was.

Emily is being bullied, I wrote.

She is me. But we know better now. We can rewrite the story.

I asked about a memory. It was from the weeks before I'd left for BYU, after Shawn had had a particularly bad night. He'd brought Mother to tears, then plopped onto the sofa and turned on the TV. I'd found her sobbing at the kitchen table, and she'd asked me not to go to BYU. "You're the only one strong enough to handle him," she'd said. "I can't, and your father can't. It has to be you."

Yes, I remember that.

I typed slowly, reluctantly: Do you remember telling me not to go to school, that I was the only one who could handle Shawn?

There was a pause, then more words appeared -- words I hadn't known I needed to hear, but once I saw them, I realized I'd been searching my whole life for them.

I lived a lifetime in the moment I read those lines, a life that was not the one I had actually lived. I became a different person, who remembered a different childhood. I didn't understand the magic of those words then, and I don't understand it now. I know only this: that when my mother told me she had not been the mother to me that she wished she'd been, she became that mother for the first time.

You were my child. I should have protected you.

Mother and I spoke only once about that conversation, on the phone, a week later. "It's being dealt with," she said. "I told your father what you and your sister said. Shawn will get help."

I love you, I wrote, and closed my laptop.

I put the issue from my mind. My mother had taken up the cause. She was strong. She had built that business, with all those people working for her, and it dwarfed my father's business, and all the other businesses in the whole town; she, that docile woman, had a power in her the rest of us couldn't contemplate. And Dad. He had changed. He was softer, more prone to laugh. The future could be different from the past. Even the past could be different from the past, because my memories could change: I no longer remembered Mother listening in the kitchen while Shawn pinned me to the floor, pressing my windpipe. I no longer remembered her looking away.

I told them I'd been poor, I told them I'd been ignorant, and in telling them this I felt not the slightest prick of shame. Only then did I understand where the shame had come from: it wasn't that I hadn't studied in a marble conservatory, or that my father wasn't a diplomat. It wasn't that Dad was half out of his mind, or that Mother followed him. It had come from having a father who shoved me toward the chomping blades of the Shear, instead of pulling me away from them. It had come from those moments on the floor, from knowing that Mother was in the next room, closing her eyes and ears to me, and choosing, for that moment, not to be my mother at all.

My life in Cambridge was transformed -- or rather, I was transformed into someone who believed she belonged in Cambridge. The shame I'd long felt about my family leaked out of me almost overnight. For the first time in my life I talked openly about where I'd come from. I admitted to my friends that I'd never been to school. I described Buck's Peak, with its many junkyards, barns, corrals. I even told them about the root cellar full of supplies in the wheat field, and the gasoline buried near the old barn.

I fashioned a new history for myself. I became a popular dinner guest, with my stories of hunting and horses, of scrapping and fighting mountain fires. Of my brilliant mother, midwife and entrepreneur; of my eccentric father, junkman and zealot. I thought I was finally being honest about the life I'd had before. It wasn't the truth exactly, but it was true in a larger sense: true to what would be, in the future, now that everything had changed for the better. Now that Mother had found her strength.

The past was a ghost, insubstantial, unaffecting. Only the future had weight.