Love situation what should i do?

ok so this girl i love was previously with this guy for 2 years but they both called it quits cause he was going to college which is like a hour away from where she lives and shes a senior so they wouldnt see each other as much so she said she was single and so in my math cl we met and like we starting talking and eventually she started to like me and i liked her so we spent time together like walks at the park and we really got close and even kissed and it was good love but she told me she didnt want a relationship cause she still had feeling for him and he always sends her love notes and wants to get back together but she says no...and so she liked me and i fell in love with her and she fell in love with me but later on she went to the homecoming dance with him and the next day he took her horseback riding and she fell in love with him again so then she told me she loves him again and wants to get back with him again but she didnt but things arent the same anymore..she doesnt end every night text wih i love you anymore..like she just cares about me but as a friend now ..and not like a potential boyfriend and like now she does alot of stuff with her ex like every weeknd or whenever she can but she does still care about me she says she still cares about me and now and then she says i love you but it sucks cuz ever since she told me she is gonna wait for him and thinks about going with him it puts me at no chance mode and like idk i suffer cuz i truly love this girl and i just wanna be with her but it seems it wont happen anymore like it was before cuz she told me that stuff like she loves him and i was her lesson cuz i didnt trust her or something like that but i did it was just my friends think she played me but i dont think she did so what should i do..keep trying or just try to forget about her and give up?