3rd update..my gf going back to her ex part?

because your the rebound guy ... your being played & yes ... your in love .. but she's in love with somebody else. As destructive as that relationship is ... she's in love with him. Your doing yourself no favours by offering yourself like that. She doesn't love you the way she loves him, time to move on ... let her go ... as hard as it is ... you'll be better off.