Confused about forgiveness vs being used

Hi guys.. u can skip the first paragraph if u don’t want to hear my long rant😊😊 but please read and answer my second paragraph🙏

so basically i have had this friend for a few years like i met her in hs and we were rly close but now we’re in college and i just found out that this entire time she’s been feeding lies to her parents abt me to make them think im really dumb or something and so they that they think this “friend” is really smart and this caused her parents to lose respect for me completely so this “friend” now never hangs out with me alone unless one of our ivy league friends are with us. Guys in reality i am not that dumb.. i feel really bad for saying this but she asks ME (the supposed really stupid person!) for help in our summer orgo class. like i get about 20 texts a day asking how to do this mechanism or this rxn or whatever crap but once i realized what she says abt me to her mom i just stopped helping…. so now i have like a million texts unread… bc i’ve been ignoring her. the thing is even in class i kinda ignore her too bc im genuinely so mad like we were such good friends and she completely makes me look like a fool and would rather hangout with the ivy league friends or give them rides instead of me just because of what she purposely portrayed me as… but she keeps coming up to me in SCHOOL not OUTSIDE OF SCHOOL idk if that makes sense… like she USES ME in school but HANGs out with everyone else.

Ok so my actual question is… when do we stop forgiving? I know the Bible says to always forgive each other as God forgave the entire world… but how do u keep doing that without being constantly used? for school or literally anything. like i dont want to be used and i dont want to be her friend anymore either. it’s not like she said sorry anyway. but im not ALLOWED to hate her.. but i do.. like how do i stop. what do i even do. i dont even know