My girlfriend and I have been together for about a year and a half now but we are having problems... im a senior in high school and she graduated last year and this summer she moved in with me and my mom and I kind of took advantage of her and cheated on her and my mom realized that me and my girlfriend weren't steady and that I was playing her so she moved back with her parents recently and they have been telling her things and now she wants to leave me because of what I did and also before we basically cut each other off from all friends and family and now she says its my fault and that I'm controlling... now she wants me to change but I don't know what to do or how to change to make this work.