Im tired of her being my bestfriend. what do i do?

ok so i have a bestfriennd and i love her dont get me wrong. but im getting sooo tired of her. she has been just a 13itch for the past 3 to 4 months. she will say shut up or laugh at my parents when they say something. and i will do anything for her like walk 55 minutes with her at 3 a.m so she can see her boyfriend(nothing in it for me) but when it comes to her doing stuff for me she complains and says oh waaa deal with it. and when people are calling her names she gets mad when i dont say anything to them but when people are saying rude things to me she tells me to stick up for myself. oh and she brings her mom into everything. if we get into a fight she calls her mom and will say mom just come get me and tell her to stop(then i get yelled at by her mom). and she is probably the most jealous person you will ever meet. i had bestfriends before her and she will cuss them out because i hang out with them. and when i try to go hang out with someone else she will say dude im done trying i try so hard but it just doesnt work we cant be besties anymore. then a couple hours later...i cant live without please i need my bestfriend. ugg im tired of it. and if shes not my top on myspace she will comment on it saying **** this i have been replaced again. i mean come on someone can have more then one bestfriend!! im just fed up with her **** i cant take it anymore. but then again there are times when she is there for me and is funn to be around(but that her is slowly dissapering). so what do i do? im just tired of being her bestfriend.