So.. me and my best friend (also cousins).. have been bestfriends for 3 to 4 years.. we did everything together.. imean everything.. she made this dance group.. and I joined.. so she had this other girl.. I don't know her buhh she thinks she better than me.. so every time my "bestfriend" mentions her name.. she bosses up and think that she's bigger and better than me(my best friend does that).. soo I asked her why she does it.. and she didn't admit it.. I was crying and everything.. she said I'm too wild.. and when she talks on the phone with the other girl she talks about me like I'm not there.. ilove her I just don't know what to do.. please help me.. :(

Doesn't exactly sound like a real friend don't you think? It takes a lifetime to realize who are true friends are, because our true friends will be around for a lifetime.

Stop hanging out with her, stop making her your number one priority. When she asks why, tell her what you just told us. If that doesn't go anywhere, you might have to start looking for a new friend.

Or maybe she is not doing it at all.
If it bothers you don't hang out with her.