If you didn't feel bad about what you did then I question whether or not you have feelings for your GF. If you really loved her and cared about her you would have at least some remorse for what you did. So the way I see it, is if you don't have feelings for her, then break up with her.
[quote name='"fakeacc1"']yeah i know i just feel like after all the time together memories what have you it would be too hard to do you kno[/quote] I know man. But the past is the past, and you have to remember people change. It's time too look to the future. If you're truly not happy in the relationship then end it. Sure, the sex was great, as you said, and you like her company. But there's more to a relationship than sex and physical company. There has to be an emotional connection between you two. I don't know what exactly your relationship with her is like, I'm just giving advice based on the information you've given me.
[quote name='"fakeacc1"']yeah i know thanks alot man[/quote] Sorry I couldn't help you out more man. I hope my advice helped in some way though