I've had that happen with a girlfriend. Not because she got a boyfriend, either. I'd known her and was close with her for eleven years. All of a sudden, she sent me a text message saying she was moving on with her life. Without me. That's the last I heard from her. No warning, no explanation. That was nearly two years ago. It happens to everyone at some point, in some way or another. It sucks every time. No matter how little time you've spent with the person, it is just about the crappiest thing someone can do. Obviously, it's worse when you have time and feelings invested. I'm sorry he's being that way. I've never been that way with boyfriends having female friends. There have been a couple of times I have had issues with girls, but, those were because they would do things that were inappropriate (and not just friendly behavior ). I hope things work out for you. But, things do happen for a reason. I know that sounds corny and cliche, but, I truly believe it.