Is it all my fault?

Okay y does everything seems to be like my fault. We quarreled again just now while on skype. She told me got another guy is trying to woo her. It's not the first time alr.. I feel that she's trying to show off? And by saying that to me ofcus I will feel insecure right. I told her what I felt on the phone. She got so pissed, and said its normal what, i would tell my frens about it too what. I don't know is it me who's not understanding enough.. Not only that...I feel like she's trying to know my guy frens. Okay maybe nothing wrong with that.. But she like also trying To know my bro. When's she is in sch, she will like get touchy with her guy frens, worse still, she will boast to me about