THE FATBOY SHOW : Why Friendship Break-ups Hurt So Much.

When Krystle Dullas's close friend left their city for an extended cross-country road trip in 2022, they vowed to stay in touch. But as life got busier, their long telephone conversations and video exchanges slowly dissipated, Ms. Dullas said.

In January, when she saw on social media that her friend visited home without seeing her, Ms. Dullas felt confused and hurt. And her inquiry about the visit received only a curt response, she said.

The two haven't spoken since.

Ms. Dullas, 37, felt as if she'd been unceremoniously dumped by someone she'd been close to for nearly five years. And while she doesn't regret losing a friend who was unwilling to make time for her, Ms. Dullas was surprised by how much the breakup stung. Indeed, cutting ties with a close friend can be as tough as splitting with a romantic partner, relationship experts said, though there's no cultural script for processing the end of a friendship.

"It was just really, really sad because you're mourning a person who's still alive," said Ms. Dullas, a sales representative at a board game distributor in Richmond, Va.

Such breakups represent an "unrecognized kind of grief," said Beverley Fehr, a social psychologist with the University of Winnipeg who studies close relationships. "If someone goes through a divorce or is widowed, there's generally support for the person — or at least an acknowledgment of the pain they are experiencing," Dr. Fehr said. "That tends not to happen so much with friendships."

Here's why losing a friend can feel so painful, and some expert tips if you're considering a breakup.