Do I think NEGATIVE about my girlfriend? or is it SHE THE WAY IT IS?

I've been in somewhat same situation where a girl didn't appreciate for who I was. I just broke up with her and gave her the stupidest excuse, just cause I know shes the bad kind of gf. She flirts, and she also calls my best friends the b word. Anyways, i'd just break up with her and ignore her for not appreciating you, and possibly using you.