It began with a missing package. One day I got a message from a stranger on LinkedIn: “You don’t know me, but I live across the street, and I think I have your package.”

Our building and apartment numbers were similar. Even our first names sounded alike. “Thank you so much for taking the time to track me down,” I wrote back. “I can come right away to pick it up.”

“Can you wait?” she wrote. “My baby is napping, and I don’t want the intercom to wake her. I’m all alone and I really need to work.”

When I picked up my package later that day, I brought her flowers from the local bodega. She buzzed me up and stood waiting by her apartment door, which was opened just a few inches, her dark brown hair pulled into a haphazard ponytail, her face, visible above her mask, looking wan.

“Thank you again,” I said, handing her the yellow tulips.

She glanced at the flowers as if she could not quite place what they were, then said, “No one has done anything like this for me in so long.”

We stood in silence for a moment. When her baby began to cry, she turned, mumbled a distracted thank you, and closed the door.

Two weeks later, we had our packages mixed up again, but this time I received hers, a large plastic bag of clothes from the Gap. When I texted to let her know, she wrote that she was too busy to come that day and asked, “Can you hold it until tomorrow?”

“Of course. Any time over the weekend is fine.”

A few hours later, she texted again. “Do you mind if came over now?”

“That’s fine,” I wrote.

Ten minutes later, she showed up wearing a black KN95 mask and bearing a chubby-cheeked, 6-month-old baby who stared at me beatifically from her carrier. My neighbor’s own eyes were ringed with deep circles; she looked wild with exhaustion.

“Do you want to come in?” I said.

She resettled her baby while considering her options. There was a new variant; everyone was wary. “I’d better not,” she said. She made no move to leave, though. Instead, she stood in the hallway, shifting her weight from one foot to the other.

“Are you OK?” I said.

She blinked before blurting out, “I’m a single mother and I work from home and my babysitter didn’t show up and my daughter is teething and I’ve been up for three nights in a row all alone.” Her mouth quivered as she struggled to keep control. “I’m just so lonely.”

“Do you have anyone nearby to help?”

She shook her head. “My family doesn’t live here and I have a rent-stabilized one-bedroom apartment so I can’t afford to move.”

I asked if she had met any other new mothers in the neighborhood who might offer support.

“No. I work full-time. I barely have time to shower. Besides, no one is really going indoors right now.” Her eyes bored into mine. “People say they understand what it’s like, but they don’t. They just don’t understand.”

I recognized the look. “I’m a single mother, too,” I said. “My daughter is grown now, but it was hard enough without a pandemic.”

“How did you do it? I’m not sure I can make it through another night.”

“I don’t know,” I said. “Somehow you just do. I remember a time when my daughter was 6, and I had a bad stomach bug. I lay on the bathroom floor at 4 a.m. trying to figure out how to get her to school in the morning. I had no one to call. Eventually, I managed to take her in a cab with a plastic bag in my purse in case I threw up. I went home, called in sick to work and slept. It didn’t occur to me until years later that the world wouldn’t have ended if my daughter missed a day of school.”

My neighbor fidgeted.

“You just have to get through the night,” I said.

She sighed, stroking her daughter’s head. “I should get going.”

I watched from the doorway as she headed off into the long evening ahead.

According to a recent study by Pew research, the United States has among the highest rates of children living in single parent homes in the world. 80 percent of those households are headed by single mothers: single mothers by choice, circumstance, bad relationships or early widowhood. Whatever the reason, I can promise you that nearly every one of them has had a lying-on-the-bathroom-floor moment, waiting alone for the morning to come.

The pandemic has left even the most connected of us isolated, searching for support. It’s not surprising that single parents have suffered higher rates of anxiety, depression and loneliness than parents from other households.

After my husband died when my daughter was 5, I was lucky to have friends and family nearby who helped. I could afford child care. We were not in a pandemic. Still, there were times when I felt utterly alone. And scared.

Soon after my husband died, my doctor found a suspicious lump in my breast. “Nothing to worry about,” she said, “but let’s just check it out.”

I lay on the examining table while she ran the wandlike transducer over my skin. Every time she hovered on one spot, I panicked and said, “Did you find something?”

“Will you please let me do my job?” she finally said, clearly annoyed.

I apologized but also started sobbing. “My husband just died, and I don’t have a Plan B. I don’t know what would happen to my daughter if I got sick.”

“I’m sorry,” she said, softening.

My husband died without a will. We were young, had no money. A will wasn’t a priority. That afternoon, I went home, called a lawyer, and soon made one, naming a close friend as my child’s legal guardian. Two weeks later, the biopsies came back benign.

The anxiety of parenting without a net didn’t subside, though. The next year, when I had to fly alone for the first time, I had a panic attack on the way to the airport. I called my friend and listed everything she needed to know about my daughter: her teacher’s name, the pediatrician’s phone number, where I stashed an emergency duplicate of a favorite blanket.

My friend listened patiently. When I stopped, she said, “You know you are only taking the shuttle to DC, right?”

Over time, I learned to prepare for certain events. Often, though, it was the smallest incidents that blindsided me. When my daughter was in third grade, her teacher had the class make Father’s Day cards. I was unaware of the project — all I knew is that she began to act out at home, culminating one afternoon in her bringing home an intricate, 3-D card she had made. With no father or grandfather, she couldn’t figure out what to do with it, so she smashed it to the floor.

One night when she was 11, she spiked a fever of 105. I couldn’t get her to pick her head up off the floor, much less swallow an adult-sized Tylenol, which was all I had in the house. It was midnight when I reached the pediatrician on call.

“Send someone out for liquid baby aspirin,” the doctor said.

“I don’t have anyone to send,” I said with an edge of desperation.

The doctor grunted, as if he couldn’t imagine how I’d gotten myself into this predicament. “Put her in a cold bath,” he said.

My daughter had grown too tall and heavy for me to carry her on my own. I hung up, covered my daughter with cool washcloths and lay on the floor beside her, still clutching the phone, while I waited for the fever to break.

Of course, there were people who did understand. Friends and family who saved me over and over. And single motherhood is not without benefits. There is intense bonding: secret jokes, made-up rituals, a deep commonality. A single parent gets to set all the rules. There’s no one to argue with over appropriate chores or the right age for a cellphone. You are inextricably threaded together.

My daughter grew up, graduated law school over Zoom at the height of Covid. Before the pandemic, we got matching infinity symbols tattooed on our shoulders because she used to say, “I infinity love you.” Bunkered in separate cities, we signed our texts, emails and birthday cards through health scares and virtual celebrations: “Infinity love.”

A few weeks after the last package mix-up, I texted my neighbor to see if she was all right.

“I’m doing OK!” she wrote. “My daughter is a joy and brings so much happiness during these tough times.”

“I’m so glad,” I replied, because I understand that, too.

Emily Listfield is the author of seven novels. She lives in New York City.

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

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