Confusion...

I'm was just sitting here thinking about something and was wondering am I the only one that found this to be disturbing in my book..
I understand how females are when it comes to their friends or acquaintances talking to their ex-lover. Even when its not really that serious. But its crazy how guys could care less. Its like fuck and pass, fuck and pass haha
Well I remember when I was in 9th grade and these two girls were basically fighting for this boy. They hated each others guts and wanted to literally fight for a boy that was playing them both really. He would mess with one then break up with her and mess with the other and still mess with the first. Man it was crazy. It was like the talk of the school. Was these girls really serious?! And to top it off he called one of them out in public like she was some hoe or something but she still stayed messing with him. I don't know about you guys but once you disrespect me then hunny you out the door. You mean not a dam thing to me anymore =]
My friend and I was talking today in school because now these girls claim to be the bestest of friends. And the one that I guess won the battle continue to be with the boy but they recently broke up. Now it seems as though she passed him on to the other girl because I know and everyone else know that they are talking.
How can you be someone's bestfriend and you mess around with the boy that she was so in love with??
That's something I just couldn't comprehend. If it was just a regular guy then I understand but no they have been together and messing around for a while so I know the feelings are there. She can say she doesn't care but truthfully she does and if your so called bestfriend has the nervous to continue to mess with him on the side then that's a problem.
Then again her bestfriend might not be telling her the whole truth about her and the boy. You know how girls are: try to make it seem as though he just pursuing her and she not messing with him.
I just want to know am I wrong for thinking this is wrong or is it really wrong? lol
I'm just confused I tell ya...confused!