Her boyfriends always hate me, What's going on?

Maybe they think they know something that you 2 fail to realize. You may be a lot better for her. That's just one case scenario. On the other hand some guys ( and girls) like to play games and depending on how close you and this girl are ( sounds like you 2 are close) they may not want you getting in the way of their ill intentions. Not every guy that meets her is going to have her best interest at heart because your invested in your friendship I know ( just like they do) your not going to let anything happen to her. And lastly It all boils down to the whole '' macho'' , ''tough guy'', exterior that most guys have they don't want you stepping on their toes.

Sometimes people act different around you in that situation because they may think you still have feelings for her and you might want her for yourself or something.

I agree with the insecurity part. Also, I think it has a lot to do with competition. Maybe they just always feel as if they have to compete

I have a guy friend that I have known for eight years. We never really dated and I don't think I ever would date him. I love him to death, and every boyfriend I've had has hated him too. I'm not to sure why so this is a good question. My best guess would be that they are insecure about their girlfriend having been such good friends with opposite sex, and wondering whether or not they've "been together"

Ill be checking back to view any other answers you get cause it might also help me out. Thanks for asking this