Sometime during London’s third lockdown, when everything was still closed, I began watching the squirrels in the tree outside my window intently. There were two of them, and all winter they chased each other around the branches flirtatiously. By early spring, they had built a nest in the crook of the tree and, whenever one of them left, the other would poke its head out, concerned. Recently, I noticed three smaller heads peeking out—squirrel babies!—and not long after that, I began relaying the whole tale as an anecdote to friends in outdoor beer gardens, which had just reopened. Three of them! Can you believe it? Amazingly, they could. They smiled politely, waiting for a punchline that never came. There weren’t many follow-up questions.

As the vaccination rollout has sped up, many of us have tentatively embraced real-world group activities again. All of a sudden, after months spent tinkering with the arrangement of the objects on my coffee table, I had invitations to a birthday party, a rooftop dinner, a girls’ reunion night, a tapas restaurant. In London, the reopening of shops and other nonessential services has been like the lifting of a thick fog. I wandered into my local bookstore, dazed and joyful, and touched all the books, before seeing a sign asking customers not to touch the books.

For many, the transitional period has been a little bumpy. A report by the American Psychological Association, published in March, 2021, found that almost half of Americans surveyed felt “uneasy about adjusting to in-person interaction” after the pandemic. The numbers did not change among the fully vaccinated. Nearly half of adults said that they did “not feel comfortable going back to living life like they used to before the pandemic.” After a lonely year, in-person socializing feels both exciting and alien, like returning to your home town after a long while away. Will everything still be there? Will you have any friends left? Will you have anything to say? Conversation, even on a bar stool, feels creaky and unpracticed. The joints need oiling. Still, there’s only so long you can workshop a squirrel anecdote. Eventually, you will need new material. You will need to leave the house.

“Our social muscles have atrophied,” the author and conflict-resolution facilitator Priya Parker, who wrote the book “The Art of Gathering,” told me recently. In Parker’s work, she often deals with groups of people who have “been through a transformative experience together.” The process by which they rejoin society after such an experience is called “reëntry,” she said. She considers the pandemic a transformational experience for everyone. Reëntry is upon us all. “There’s extraordinary anxiety in that phase, and it’s not illogical or irrational anxiety,” she said. “We have to ask the questions that reëntry asks. They start with practical questions like, Do I wear my mask? Do I say yes to this invitation? Do I take my children even if they’re not vaccinated?” What seem like logistical queries are actually “philosophical and existential questions,” Parker said. “Like, Who are my people? How do I want to spend my time?”

A year of unnaturally restrictive gatherings has created some well-intentioned but baffling situations. Parker told me about a three-year-old’s recent birthday party, in which the host had asked everyone to wear color-coded T-shirts according to their vaccination status. “She thought she was helping to create a sense of codes and norms to make everybody feel safe,” Parker said. “But the backside of that is that you’re also creating, like, a caste system.” Parker believes that there’s a searching quality to our gatherings now: Am I doing it right? “Sometimes we try out codes and then people get really upset because they’re not the right codes,” she told me. “But they’re trying to solve a real need. It’s just you can’t figure out the codes until you’ve kind of tried a bit. So I think there’s going to be a lot of crashing into each other over the next many months.”

All that trial-and-error crashing around is enough to make you want to stay inside, where the codes are known. Inside, you are the code. Recently, I spoke with Arthur Bregman, a psychiatrist in Coral Gables, Florida, who has been using a new phrase to describe our desire to stay at home: “cave syndrome.” Bregman has been seeing patients for more than forty years. As COVID vaccinations have become more commonplace, he has noticed a reluctance to venture out again among his patients, even the fully immunized. “People can’t shake the anxiety,” he told me. “They feel fearful and insecure about the uncertainty of the situation. So they’re very kind of timid and uneasy. And they have excuses. Some of them, more excuses than Campbell’s has soup.” They worry over stilted conversation as much as new variants. “I have people coming by saying, ‘I had trouble before, I think I forgot how to do it,’ ” he told me. “ ‘I don’t know how to socialize.’ ”

Bregman has theorized that people experience cave syndrome at different levels of severity, with mild queasiness at the thought of a trip to the grocery store on one end and full-blown withdrawal from friends and family on the other. “For some, it is caused by panic, anxiety, and other comorbid disorders,” he wrote in a blog post on his Web site. “For others, it mirrors Stockholm syndrome where captives develop a troubling bond with their captors.” Much of what Bregman was saying made perfect sense. We have been told for a year not to socialize in groups because of a deadly virus about which little was known. We have honed our habits and defenses accordingly. I thought of a man in my neighborhood who would hold his arms out, hands balled into fists, whenever anyone passed, to make sure that they maintained their distance.

Shortly after outdoor dining reopened in London, I went to a pub for a friend’s birthday. I had put on a real bra, jeans, lipstick, mascara, and earrings, taking an absurd amount of time to get dressed. I felt preposterous, like I was wearing a costume that had been sold with the label “Woman Meeting Friends.” At dinner, people were fixated on the performative aspects of getting out. “We’ve become obsessed with jeans,” one friend told me, about a conversation she had been having with her flatmate whenever she contemplated leaving the house. “We talk about jeans all the time. Like, What are jeans? Are we wearing the right jeans?” Later, a friend told me that she had started applying makeup again for special occasions, but only to the top of her face, above her mask. Another hoped that the future would be “bra-optional, because that’s how I’ve been living my life.”

Those venturing out of their bubble often describe a feeling of watching themselves socialize. “I’m very conscious about what I’m saying when I’m speaking aloud,” one friend told me. “I immediately apologize for myself, like, I haven’t really talked to anyone in a long time—I’m sorry!” Another friend confided that she was acutely aware of her partner sitting next to her, listening to her repeat the same anecdotes in every conversation. “There isn’t any gossip, so I have to recycle stuff I heard a year ago,” she complained. Worse, some of the joy of gossiping seemed to have dissipated. Who could get worked up about someone’s wedding drama these days? “I can’t say anything mean about anyone anymore,” she observed, sadly.

Newly accustomed to socializing online, many are rethinking their extracurriculars. Shanine Salmon, a thirty-three-year-old assessment coördinator in London, runs a theatre blog called View from the Cheap Seat. Before the pandemic, Salmon would regularly attend three or four plays a week after work, squeezing into the nosebleeds in crowded West End theatres. Now she has a new hobby: online quizzes. “I don’t know if it’s going to be easy,” she said, “for me to just go, Great, I’m going to go to the theatre again, and I’m just going to be in these cramped spaces that have poor air-conditioning and all the other things that weren’t great to begin with.” (Another blog she runs, Buffet Bitch, has also been put on hold.) “You really have the question, What is the aim of going out? And do I need to do it as much?” In my own life, I’ve had to stifle an urge to suggest a structured group activity after about an hour of in-person conversation. The idea of double-booking—drinks with one friend, dinner with another—made me sweat. My stamina was down. Could we just text each other while watching a movie instead?

The pandemic has spurred a “recalibration of priorities and of what matters,” the British psychoanalyst Josh Cohen told me recently. Cohen is the author of the 2019 book “Not Working,” which argues for the unexpected benefits of inactivity. During the first lockdown in the U.K., he observed a kind of giddiness in some of his patients, an “opening up of the possibilities of life within a narrow circuit.” Some individuals’ private lives had benefitted from the slowdown. “Some people have let themselves discover empty time, and actually inhabit it, and not be pulled into the ever-present temptation to fill it,” he said.

For millions of Americans during the past fourteen months, of course, there was no empty time. In hospitals, and nursing homes, and pharmacies, and grocery stores, many worked harder and longer than ever, alongside the virus. But for a large percentage of the working population—more than a third, according to a survey by the U.S. Census Bureau—the onset of the pandemic forced a retreat into the home. For office workers freed from the office, the norms of capitalism were suspended. They no longer had a commute or a boss who hovered over them. They could work from anywhere, and many did. In smaller towns, in bigger houses, closer to family they hadn’t spent more than a week at a time with for years. Many young people moved in with their parents temporarily, forming multigenerational working communes. Others left for adventures they had long fantasized about. A friend of mine spent this past year working out of Airbnbs, exploring new places at night and on the weekends; another moved with his partner to a remote part of Alaska. As employers begin setting dates for a return to the office, “there’s a growing awareness that things will soon be returning to normal,” Cohen told me. “Kids will be returning to school, and partners will be returning to work. Households will basically be scattered again.”