Please answer~friend issues...?

Ok so me and this girl have been best friends since like ever and now she is being very iggnorate, bratty ect; We said never to let a guy get in the way of our friendship and obviously she did. Me and this guy have been like good friends forever and she went and dated him?! i mean she could have told me..but her signiture like on her fone is like i am awesome or money sign and she acts so stubbornn...we ALWAYS used to joke around with eachother and now all of sudden she cant take it?! then i get in trouble for doing bad things when she is doing an equal share, if not more. should i just not be friends with her anymore? i tried tlking it out and she said something about we cant ask out boys or sometin. wat the heck