So I recently seen on FB that a girlfriend of mine and a really good guy friend/ex boyfriend are friends. I don't know how they know eachother, but they are really flirtatious with one another. . Him and his family are still close to my family, we were friends long before we dated. She is a girl I met through other people but have developed a good friendship with. . In her past relationships she has been the psycho girl and is really different when you know the real her. . Should I tell her that he is my ex, and that she shouldn't go there. Or should I tell him how she is? I don't want him to get the impression that I'm jealous, or her to think I'm trying to mess things up and ruin our friendship. I just know how they both are and see this heading South real fast if anything comes of it.