Leaving a group can mirror the experience of breaking up with a partner.
“Both involve brain regions that are also associated with physical pain,” says Dr. David Marcus, a faculty member of Washington State University’s psychology department. People experience a type of social pain when they are rejected or shunned by a group, similar to the pain experienced when a couple breaks up, whether it’s being kicked out of a high-school clique, or falling out with your family. This is compounded by the fact that a group can become part of a person’s self in much the same way as a romantic partner can, Marcus says.