Maybe he is good-looking, but she is not in love at all. She used that man as an outlet. In other words, she is using him.

There are many reasons why friends don't like to see them together, such as: dissatisfaction with her boyfriend (mostly because she urgently needs to vent, but she agreed casually for the time being), good face (if she likes his inner beauty and this person has a lot of face, then she usually doesn't like high-profile, let alone taking advantage of the relationship), shyness (but she doesn't have much feelings for him, so it has nothing to do with shyness), ambiguity (he doesn't), so find someone to fill it first.