Well that would be my other guess, that you're just having problems with this girl, compounded with issues from another relationship. All I can say is communication, communication, communication!!
Anything to do with a relationship, within reason, can be solved with just being honest and talking. Easier said than done however...
This kind of reminds me of a situation I was in not too long ago. I had a real low sex drive because of stuff my ex wasn't willing to do, despite months of patience on my part... can I just ask, do you trust this girl? Do you think you're worried you're gonna get burned again?
Sex is just sex, and I feel the most enjoyment you get out of it is who you're doing it with not
what you're doing. Trouble in the bedroom normally means it's trouble out of the bedroom.