Is my friend a good friend to me?

so i don't like when she i gloomy so i try to cheer her up but she never smiles and when her other friends aren't here she hangs out with me and we laugh uncontrollably but when her friends come she leaves me alone with my other friends when i tell her about how i don't like somebody she tells them so i cant really trust her and she is rude to me she says that i look fat sometimes and she and her friend tell me to go away and other people say that I'm her dog on leach but she can be sometimes my friend cause she says that I'm better than her other friends and she can be helpful too so I'm confused help me!!!