Man, your situation sounds very, very familiar. I guess I am still in a similar situation. The truth is, if you can't show her any affection any more something is not right. You you have to make a decision some time, one way or another. you can't continue to do it to your self or to you G/F. All girlfriends/wifes deserve to be have love and affection and be treated number 1.
I know I could not give this to my last G/F, I knew she was not the one. Alhtough I hurt her, I felt I had to step aside and not lead her on any longer.
Sometime it is hard to tell if you are in love, but you always no when your not.
Which are you?
Stop wastin time, life is too short!