I think my friend was using me

a little over a year ago now i moved out of my grandparents and into my moms. my grandma was a narcissist and through the healing process i can be honest it was rough. for me and everyone around me. i’ve gotten better and though i’m still healing i can say i’m not rude for no reason anymore. my brothers gf jasmin moved in recently after getting in a “fight” with her parents. since then it’s been nothing but drama. she started fights with my brother and me daily. she’s fully isolated him from talking to anyone. the other day (about a week ago now) she sent me some messages talking badly about my mom and i told her about it. my mom had a talk and told her that it was not appreciated being that we are giving her a place to stay. after some long thought i realized that she used the trauma and event i told her about when staying with my grandma and fed them back to us. i got my car insurance in my name and she threw a fit about me changing it because she would no longer be able to drive it. she would constantly take it without asking and then make me put gas in it. she had me buy her food daily almost every meal every day. she is now not talking to me and telling everyone i’m toxic and an attention seeker. i tried everything to be there for her during the love and just am really hurt that she would say these things i was there when she screamed and cried and felt nothing at all. i got her more hours when she asked me too and then she would post “f this job” and not show up for the shifts she requested. i don’t know what to do anymore. she’s making me look shorty to everyone she knows and i want to say something but i know i can’t.right now when i look at her i just see red. and i’m overwhelmed with anger. because she taking my brother from us and treating us like ***.