PLEASEE 10 POINTS FOR BEST ANSWER?! i have no true friends.?

ok, so ive been really close friends with this girl sabrina since 5th grade. she's always been a shallow person, and long story short, i went to camp with her this year, she did the most horrible things to me. she made me cry everyday. and she affected me. currently, i have been very depressed because of her 24/7, cuz me and her used to be really close, and now she's telling everyone she just felt bad for me, that's why she became my friend. i cant be;ieve it. she's the MOST HORRIBLE PERSON EVER. i have two bestest friends, jenny and holly, who are also close friends with her. no matter what i tell them, they never take me side. they always take sabrina's side. sabrina, she's ugly inside and out, and she's on the heavy side. wen i was friends with her, wen she got jealous, she would make everyone that was prettier and skinnier than her, feel bad about themselves, like me. i am like 200 pounds lighter than her, and she always made me feel bad about myself. she still does. holly and jenny never had the guts to stand up for me. and to everybody that picked on them, i practically destroyed them. holly and jenny are friends with sabrina, and for more than ANYTHING, i want a true friend by my side, who will stand up for me. but that's not happening any time soon. please, anybody, any advice?