Is this bad? Mean? not-cool?

Okay so I have really liked this girl for a while, but she has been dating this absolute idiot stick for a while, and knows how he acts to other people. So we started talking about ti and everything, and then she fell for me and broke up with her BF. Her and I are going to be hooking up soon, but was this a mean think to do to the idiot stick? I mean he was racist (she is black), he was obnoxious, rude, unthoughtful, untrustworthy, and he completely ignored her when he was with his friends.