The last time anyone celebrated Valentine’s Day, most of the world was carrying on as in any other year: Couples met at movie theaters, bars were full of dates and restaurants were brimming with lovers sharing candlelit dinners.

Twelve months later, the year’s most celebrated date night looks drastically different in the shadow of a pandemic that has killed millions, battered economies and upended daily life. Theaters are closed. Most restaurants have limited capacity, if any. Many people are more reluctant to meet strangers or strike up casual conversations.

But glimmers of hope have persisted — for the vaccine rollout, for the end of a painful winter and for new relationships among all kinds of couples, some who found each other in traumatic circumstances. These four couples managed to fall in love, and in some cases get married, despite the odds being stacked against them.

A cab ride with consequences

A few months before novel coronavirus cases started to appear, a trip to the Arabian Sea and a taxi brought together Maria Saavedra, 37, a law administrator from Luxembourg, and Abdala Ahmed, 27, a businessman from Alexandria, Egypt.

In October 2019, Ms. Saavedra, feeling sad and frustrated with dating, decided to join her friends on a trip to Dahab, an Egyptian coastal town known for diving. Ms. Saavedra said she was sitting alone near the water, reflecting on her troubles, when Mr. Ahmed suddenly appeared.

Like Ms. Saavedra’s friends, Mr. Ahmed had been diving nearby, and the two shared a taxi cab back to an area near her hotel and his dive center. On that ride, Mr. Ahmed started up a brief conversation — and when they ran into each other again in the same area the next day, he asked for her contact information.

“Since that day, we haven’t missed a day talking or chatting,” Mr. Ahmed said.

By December, they were in a relationship, and Ms. Saavedra visited Mr. Ahmed in Alexandria that month. The pair had planned to reunite in the spring, but were thrown off course by the pandemic. They spent the next nine months apart but in near constant communication, Mr. Ahmed said, consoling each other through hardships, lockdown and home-schooling Ms. Saavedra’s two children.

“I don’t know how I would have done it if I had not met him,” Ms. Saavedra said in a video interview. She turned to Mr. Ahmed, saying, “You saw me at my lowest in life, you really did.”

By September, Ms. Saavedra was able to join Mr. Ahmed in Egypt. He proposed in Dahab, and they were married in Alexandria in December. While they currently live on separate continents, Mr. Ahmed plans to move to Luxembourg, Ms. Saavedra said, adding they will, eventually, have a second wedding in Europe. “I think the reason we have lasted was because we always tried to be thankful for having met, instead of questioning that we were separated,” she said.

A romance built on social media

Though Greg Marshall and Jade Phan met as college students near Seattle in 2018, they didn’t get to know each other until March 2020, when the pandemic forced them to attend classes remotely, separated by thousands of miles.

Mr. Marshall, 20, and Ms. Phan, 22, had both transferred from Everett Community College to Washington State University, and found themselves taking classes, doing class work and socializing online. With Mr. Marshall in Seattle and Ms. Phan in Can Tho, Vietnam, they initially bonded on social media, over a photo of a miniature pool table that he shared on Instagram, linking with her interests in miniature models.

The post started a relationship based on daily FaceTime calls, text messages and Snapchats between them, they said.

“Because of the time zone difference, I would stay up all night just to talk to her,” Mr. Marshall said. “I felt like Jade was right there with me the whole entire time.”

They remained hopeful that, despite the pandemic, travel would open up again. By July, Ms. Phan was able to take a flight back to the United States to begin classes and to be with Mr. Marshall. Their reunion at the airport was also shared online — the video of their first ever kiss has been seen more than 150,000 times.

“The more I know about him, the more I know that he’s the one for me,” Ms. Phan said.

A voice leads to love

Standing against the blooming cherry blossoms in Central Park in April, Carolina Morales lowered her mask so that her date, Joe Weel, could see her face. It was an important moment for the Manhattan couple, who met on Bumble two weeks earlier and decided to give dating an honest try during the first wave of the pandemic.

Before meeting in person, Ms. Morales, 29, a lawyer, and Mr. Weel, 27, a software engineer, got to know each other over the phone and through video chats, and the couple realized their values were aligned, Ms. Morales said. The pandemic had kept them cautious, talking only remotely, but Mr. Weel said he could hear something special in Ms. Morales’s voice.

“I really like the voice of a woman that matters a lot to me, because you have to hear it your whole life,” he said. “This one is good.”

Over the next several months, the couple replaced virtual dates with outings to Governors Island, Roosevelt Island and other parks across the city, and often cooked for each other. In a year in which relationships were pushed to their limits, Ms. Morales and Mr. Weel said they were grateful to have found each other. “We feel terrible about all the tragedy that happened this year, but for us, it’s really been the best year of our lives,” Ms. Morales said.

Something new after decades of experience

When lockdowns began last March, Vickie Green started making masks and offering them to the senior members of her church in Elizabethtown, Ky.

One was Garry Knight. They had known each other for 16 years, but the small gesture led to texting and phone calls, and for weeks, Ms. Green, 67, and Mr. Knight, 74, bonded over their love of gospel quartets and travel. Mr. Knight asked her on a socially distanced date, and the pair met at Chick-fil-A, where they parked their cars and talked for three hours, Ms. Green said. Around that time, she said, her granddaughter had noticed a new pep in her step.

Both Mr. Knight and Ms. Green had lost their spouses in recent years, and found that they could work through grief together and share a newfound joy. “After a couple of weeks, I realized I wasn’t crying myself to sleep every night,” Ms. Green said. “That’s a hard thing to go through, losing a spouse of 48 years. And Garry had been married 49 and a half years. Together, we’ve got about 100 years’ worth of experience.”

In June, Mr. Knight proposed. Two months later, they tied the knot in a socially distanced ceremony. Mr. Knight said the couple had learned a new lesson in the pandemic. “It could be found anytime, anywhere,” he said. “Nothing has to stop love.”