Im in the exact situation now, i know exactly how you feel. i was just like you, didnt commit as much as my gf and now she changed and also blaming me. we always fight a lot and she always says we are not gonna last, but we didnt break up though. even when she is hurt from some mistake i did, she still wants me back hoping that i will change. but now i still havent and we are still fighting, instead of being sad now, she's always just fed up of me and tell me that she wants to stop being with me soon. she just asked me to change right now, and im trying my best to do that cause i dont wanna lose her. maybe what you should do is show her that you care, do some little things or gift her something that she would like, show her that you care. after we fight, i would sometimes take her out and buy her favorite food and she'll cheer up. when she is sad or something bothering her, you have to attend to her quick and cheer her up. all these little things really matter. maybe she'll remember all those good times she had with you and give it another chance. just dont make the same mistake again after that and give her the attention she needs. Good luck bro!