When the lockdown started in March 2020, my husband and I decided to quarantine with our two youngest children, then 15 and 12, at our house on Martha’s Vineyard. We arrived on March 15 and settled in for a long stay, unpacking sweaters and boots, textbooks and cellos.

My husband set up his home office on a card table in the living room, rising at 4 a.m. to pace and worry over the markets. He chopped three different kinds of wood and built gorgeous fires. He made me whiskey sours as the sun set (we believed reports that whiskey would kill the virus). Our older daughter learned to make gnocchi; our younger daughter learned to play Fortnite. We delighted in the off-season use of our house and seeing the island for the first time in late winter light.

A week later, on March 22, at 6 a.m., my husband told me he wanted a divorce. He packed a bag, got in his Jeep and boarded a ferry. We had been married for nearly 21 years.

When he reached New York City, he laid out his narrative: He thought he had wanted our life but didn’t. He thought he was happy but wasn’t. A switch had flipped. He didn’t want our house or our apartment. He didn’t want any custody of our children.

I had no idea he was unhappy. My husband had been a man who went to bed at 9 p.m. and tracked his sleep cycles on a phone app. He was the first to leave a dinner party. He worked, played tennis and came home and watched more tennis on television. He wasn’t affectionate or adoring, but I felt a current of abiding love. He never flirted with other women in front of me. We didn’t bicker. He seemed content and invested in our life. He designed an addition to our garage and planted blueberry bushes in the year before he left.

There was another woman, as there often is when men leave. Her husband called me the night of March 21 as I mopped the kitchen floor after dinner and left a voice mail message: “I’m sorry to tell you that your husband is having an affair with my wife.”

That night, my husband was apologetic and regretful, saying he loved me and that the affair meant nothing. But by dawn, as he announced his departure, he looked different, resolved. His green eyes were icy.

The rest of the story is filled with more clichés. He left the year I turned 50, the year he reached a pinnacle of professional success at work. He bought a sleek new Manhattan apartment, hired a well-known divorce lawyer, and treated me with a consistent lack of empathy or sentiment.

What’s different about my story is that my marriage exploded at the dawn of a pandemic. It was early in the crisis when he left. We were dousing our hands with Purell, wiping down packages, using gloves at the grocery store, but not yet wearing masks. We were facing many unknowns, including how deadly the virus was, how long schools would be closed, when we could expect a vaccine. We were scared, and I relished the safety of my marriage intensely. And then my husband was gone.

I had a home, money, an isolated location to quarantine — I was safe by every measure. But my partner, who promised to protect me and our children, had disappeared overnight. The people who would have propped me up, fed me, helped with the children — my family and closest friends — could not get to me during lockdown. They wept with me on the phone, but I woke up every day facing the fear and pain on my own.

I decided not to drink, knowing that it would make me sadder, but I also found it hard to eat. Within weeks I had shed 20 pounds, the self I had come to know over two decades of pregnancies and family life.

I also had no information about my husband and why he had left us. After the generic statements about his unhappiness, he gave me nothing — no explanation for what was lacking in our marriage or in me, how long he had felt this way, or even a declaration of feelings for the woman he was seeing. He refused to see a therapist with me. Within a week, he had stopped answering my phone calls. His brother and sister also stopped communicating, saying that to support him, they could not be in contact with me.

Had life been normal, had we been in New York, had I been able to run into him on the street and make him look me in the eye, maybe I would have some understanding of what was happening. But I was on my island, and he was on his, and I knew nothing, only the shock of his disappearance.

Ironically, it had been my husband’s steadiness that made me fall in love with him. We met at a corporate law firm where he was a senior associate, and I was a junior associate assigned to his group in my second year. He was a great lawyer with a quick mind, able to supervise a dozen deals at a time, thoughtful and methodical in his left-handed markups of legal documents. He was tall, blonde and lean, a similar silhouette to my father. He wore suits and rolled up his shirt sleeves as he worked. He was a grown-up.

When he walked into my office, shut the door and kissed me, I was done for. He was intent on marrying me within weeks of that kiss, pledging to take care of me, to step into my dead father’s role as my protector. And we did marry, within the year, both of us (I still believe) very much in love.

My husband’s reserve was also appealing to me. The men in my family were moody and had tempers. My husband did not believe in yelling or even fighting. His voice was always low, often almost a whisper, and he refused to engage in an argument. Our home was calm, free from conflict, and that felt like a victory to me, a smug sense that I was living a superior life.

But a rebellious past lurked behind my husband’s calm exterior: teenage brushes with the law, trouble in school. There were many women in his wake and stories of some of them stalking him, unable to accept his rejection.

This narrative was sexy to me, the former rebel dressed in a suit, the problem high school student landing at an elite law firm, the heartbreaker. But when I think about what happened, I think about this part of him. The bad boy in him shedding the choking uniform of husband and father as abruptly as he had adopted it.

Almost three years later, I still have no understanding of why my husband left. His strangeness only increased, becoming an adversary in the divorce process and, while kind with our children and occasionally in touch with me by text, more resolute in his desire not to share custody or daily parenting.

As the pandemic dragged on, there was so little social interaction and information flow that I heard nothing about him from anyone. I don’t know if the other woman is still important to him or if she didn’t matter at all. I don’t know if he cheated throughout our marriage or if the affair was his first betrayal. I don’t know if he changed abruptly or if I was sleeping with a stranger for two decades.

I could have hired a private investigator, could have called the husband of the woman he was seeing, could have pursued my in-laws for answers. But all these roads felt sordid, like I was trading my dignity for scraps of information. I had to figure out how to move forward without knowing.

To have empty spaces when you try to remember and make sense of your past feels like a form of amnesia. Or like watching the beginning and end of a movie, and missing the middle, essential pieces of the story.

I have no secret to share about how to move on without answers. I walked a lot, a form of meditation that made me feel like I was moving forward. I took on more legal work, cooked for my children, walked our dog, bought new rugs. And eventually, after many months, I found myself on a road that had less of a relationship to his, and I stopped looking backward and sideways, only ahead.

I sometimes see him from afar in our shared city neighborhood. He looks familiar, his posture and gait, his sandy blonde hair and orange sneakers, and my heart leaps a little at the sight of him. But then I remember he is a stranger, and I walk on.

Belle Burden is a lawyer in New York City.

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