My boyfriend broke up with me the week before they found my neighbor. The breakup happened in the evening; I had spent the day grocery shopping because the World Health Organization had just declared a pandemic.

Determined to remain optimistic, I was making chicken soup and blasting Motown when my boyfriend walked in looking pale and pained. I took one look at him and knew he either had a tragic update about coronavirus or our relationship was about to end.

It takes a particular kind of crisis to make your boyfriend breaking up with you the better news. As we hugged goodbye, he said, through tears, “There’s a social distancing joke in here somewhere.”

The breakup surprised me, not only because the timing was horrific, but because I thought we still had a relationship to salvage. We had been together for six months and were good to each other, though we moved through the world in very different ways. I was tempted to chalk it up to the pandemic and hope he would change his mind. I drank two shots of whiskey and woke up with stomach pains and diarrhea.

Two days later, my symptoms persisted. I didn’t know if it was a bug, coronavirus or the physical manifestation of emotional turmoil. The symptoms got worse: I thought I had a fever, but my thermometer was broken, so I slid a meat thermometer under my tongue, which seemed inaccurate and had a pointy tip that hurt. I thought longingly of my now ex-boyfriend in his apartment a mile away.

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After a breakup, I usually try to reassert my independence and surround myself with friends, but now that was impossible. I worried that asking my ex for help so soon would seem needy, but I was too sick to care, so I texted him.

When he showed up on my doorstep with Tylenol, Gatorade, Imodium and Pedialyte, I felt overwhelming gratitude. Was this a promising sign, or was he just being a mensch? The pandemic had wiped away the normal rules of a breakup, and we were in murky new territory.

A few days later, I heard noises in my hallway and opened my door to find two E.M.T.s knocking on the door of the apartment next to mine and trying the handle.

“When did you last see your neighbor?” one asked.

“I don’t know,” I said.

“His son called because he hasn’t heard from him in a few days,” she said.

My neighbor was a man in his 80s (though he looked younger) who lived alone and used to put a chair out on our building’s narrow terrace in the summertime, where he would sit and read.

When the firefighters arrived, they went through my apartment to gain access to my neighbor’s through the fire escape. I opened the windows and doors for them so they wouldn’t have to touch anything, then returned to the hallway and heard them report over the radio that he was dead.

My across-the-hall neighbors and I exchanged a glance of shock and shared responsibility.

When the firefighters emerged, I asked how long ago my neighbor had died.

They said they wouldn’t know until the medical examiner arrived.

I had a sinking feeling. By touching the building’s door knob a week earlier, had I passed on a virus to my neighbor that I didn’t even know I was carrying?

Overwhelmed by this bleak reality, I became consumed by a kind of panicked mania and began baking banana bread as my neighbors and I waited for the medical examiner. He arrived when the bread was in the oven, a cheerful man who told us the body already had begun to decompose, so it had been more than two days. He showed my neighbors a photo of the body on his digital camera so they could identify him, then said, “Wow, something smells good! Are you making cinnamon rolls?”

My neighbor dying alone in his apartment felt like a harbinger of more grief, and I was suddenly scared of being alone. I texted my ex to tell him what happened and to ease the unbearable loneliness this death had unleashed in me. We talked. It made me want to save him some banana bread.

When I developed a fever and cough a few days later, I worried for the firefighters who had been in my apartment. My ex lent me his thermometer and tried to reassure me that the firefighters were certainly encountering the virus in other places.

Although my ex and I lived alone in separate apartments, our continued contact meant we were effectively isolating together, ushering in a new relationship gray zone. We talked every day. He offered to do my laundry. And one night, after I was feeling better, we ate tortellini and watched a movie. We weren’t worried about infecting each other because we had been in contact all along.

No longer romantic partners, we had become pandemic partners. Maybe, I thought, our relationship was on pause like the city, like the world. Or maybe, like so many couples, we were being kept together out of fear of being alone.

My ex didn’t like to be alone, so I knew isolation would be hard for him. He was always socializing, biking, traveling, planning. Our first months of dating rolled over me like a tsunami: He gave me a toothbrush on our second date and a drawer in his bedroom the second month.

Within four months, we had gone on three vacations and met each other’s families. But I worried that we had moved too fast without having done the slower work of really getting to know each other.

Sure enough, as we approached the six-month mark, we started to see how we perhaps weren’t so compatible after all. While I wanted to analyze people and bare my soul, he wanted to talk about gadgets and problem-solve. I didn’t know if these were simply differences to adapt to (I’m an artist; he’s an engineer), if they indicated a deeper problem (would we not have enough to talk about?), or if, as he wondered aloud toward the end of our relationship, he didn’t want to bare his soul because he wasn’t ready for something serious (could he get ready?).

If we could just slow down, would we still have a chance?

Now, slowing down was government mandated. Maybe isolation, with its solitude and time for reflection, was bringing us together again? Now that I had stopped pushing for intimacy, might he open up and offer it?

Not really. And as my hopes for us shrank, my fear of being alone grew. I didn’t know what to do. If I stopped seeing him, I wouldn’t spend time with anybody for who knows how long. I was afraid of missing him, since I already missed everyone. The sirens began to blare more frequently outside my window, and I urged myself to accept the strange terms of our relationship so that it wouldn’t have to end.

Until one night, 18 days past the onset of my symptoms, when he suggested I come over to bake Mexican wedding cookies. I felt encouraged by the title of the cookie he had picked (the “wedding” part), and I brought over renewed hope along with a load of dirty laundry. That night, we finally discussed our gray zone.

“What are the rules of a breakup in a pandemic?” he said. “No one knows! We’d have to go back to 1918 and ask.”

He did open up that night, but only to reiterate his lack of interest in engaging in the heart-to-hearts I craved. When he said, “I don’t think we would make each other happy in the long term,” I finally agreed.

Isolation hadn’t changed either of us; it had only clarified what we shared and what we lacked. Our mutual caretaking didn’t change the fact that when I was with him, I felt lonely. I knew then that reliving my disappointment in our relationship every time I saw him was too difficult, and I had to face being alone. I told him we should stop talking and rolled my suitcase of clean clothes home, crying the whole way.

Yet being alone has its pleasures. I’m listening to Jane Austen audiobooks on my daily walks. Absorbed in her exacting social commentary, I feel engaged and free. It has taught me not all solitude is accompanied by loneliness, and it reminds me of how my neighbor used to read his book contentedly on the terrace.

When the C.D.C. recommended wearing cloth masks, I ordered an extra one to give to my ex when I finally return his thermometer. While I’m no longer afraid of being alone, I also know that no one is self-sufficient, especially now, and that he and I will be there for each other for however long this lasts. Caretaking is the part we always got right.

Sarah Rosen, a writer, actor and filmmaker who lives in Brooklyn, is the author of “Kosher Porn.”

Modern Love can be reached at modernlove@nytimes.com.

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