Linda Waud and Charles “Ben” Waud dated through most of high school and a year of college, and then went their separate ways.

It wasn’t until they bumped into each other at their 35-year high school reunion that he told her, “I guess it’s time for us to talk.”

Shortly after the reunion, they got married, and the Florida couple has been inseparable for more than two decades.

“Yes, this can be a beautiful life,” Linda Waud said.

Now, mostly because of social media, more couples are experiencing the rekindling of high school and college romances, though not as many are encountering the happily-ever-after ending that Waud and her husband now have.

A study by Nancy Kalish at California State University, Sacramento, which began in 1993 and is ongoing, found that of the 4,000 participants who found their way back to old loves, 72 percent of them were still together. If they were married at the time that they rekindled their romance, the success rate was just 5 percent — if one or both didn’t leave their marriages. The success rate for those who left their marriages jumped to 72 percent. And, if they returned to the first love they ever had, the success rate was even higher: 78 percent. If they married their lost loves, the divorce rate was just 0.4 percent.

Rekindled romances appeared to be even more passionate than romantic movies would suggest: 71 percent of those in the study said their reunion was the most intense romance they’d ever had.

“These romances are a lot faster: They meet for coffee, and then they go to a hotel room,” said Kalish, a professor of psychology.

It happened very quickly for Megan McDonald, who dated John McDonald in high school but had a bad breakup when he went away to college.

Over the next three years, they didn’t talk but constantly asked about each other via mutual friends.

When Megan bumped into John at dinner at a friend’s house, they realized they had to be together.

“We made the decision right then and there, and decided that if it was going to be real, it needed to be real, because neither of us lived in the same state,” Megan McDonald said.

So they made the quick decision to date long distance for two years until they could rearrange their lives to be together. Now, the couple lives in Chicago. They have been married for 10 years and have a 5-year-old and a 4-month-old.

There is an unfortunate side of meeting an old love a few years or even decades down the line.

Many of them are in new relationships, Kalish said.

The internet has made finding these old loves very casual. A simple email or Facebook message doesn’t hurt and isn’t as suspicious as a letter or phone call, she said.

But that initial message can lead to another, which eventually could result in a meeting and an affair.

“These people weren’t looking for affairs. They never cheated before, and they never cheat again,” Kalish said. “Before you know it, all the emotions come back, even for a happy marriage — they don’t expect it.”

The majority of the people in the study who reconciled began with an affair.

Decades ago, such couples didn’t meet until their children were older, mostly at reunions. But today, they’re reconnecting when they’re younger because it’s easier to stay in touch or to find each other through Facebook or other social media outlets.

That usually means the couples are bringing young children into their affairs. But these aren’t the only issues to consider.

If the couple miss out on years of each other’s lives, they often feel resentful that they lost this time and that the other person gave those years to someone else. Many times, they can’t or won’t have children with their old loves, Kalish said.

Despite those issues, the couple can try to make it work — and many of them do, but they need to realize that they’re different people than they were in high school, said Rachel Sussman, a licensed therapist and relationship expert.

“When we think back on those memories — especially high school and college loves — we were carefree and looking beautiful and thin and happy — and we have an idealized idea of what love looked like, and our brain naturally does a trick on us,” Sussman said. Instead of thinking about the problems in the relationship, you think about your passion and how much better that relationship was than all of your later relationships.

But the good news is that research has shown the more you have in common with someone, the better the chances you have of succeeding in a relationship. You most likely have much more in common with your high school or college love than you have with someone whom you randomly meet online, Sussman said.

Sometimes, that is exactly why these relationships have such great odds: The couple tried dating other people after high school or college and realized that the alternatives weren’t so great, said Randi Gunther, clinical psychologist, marriage counselor and author of “When Love Stumbles.” Or maybe they married and then divorced, and were trying to figure out what to do next. And they started wondering what ever happened to their first love, who usually was a very pure love, free from the practicalities of financial or other restrictions.

The phrase “absence makes the heart grow fonder” could also apply here, Gunther said.

“When people fall in love from their hearts, and not from practical choices, those loves never go away, especially when they occurred when they were not yet bruised or cynical,” he said. Couples who reconnect describe it as “coming home,” she said.

But they shouldn’t neglect to have real conversations about their lives as they are today, as opposed to simply going back in time, Sussman said.

“The early dates are really exciting because you’re playing catch-up: You have those stories of what it was like to go to prom together,” she said. “But then, you have to play catch-up and use the same criteria of dating someone new. Do you have the same life goals? Finance goals?”