I have been in a relationship with my girlfriend for almost 3 years now and we used to always have sex (2-4 times a week), and over the last year or so its been dry spell after dry spell, maybe once a week for a couple of weeks and then maybe once a month or maybe once every two months and it changes all the time each time after we have sex and she never initiates any more so I have to all the time now but when I try all she says is nah, nah and when I finally get to touch down there even though she says no she is really wet and when this happens we have sex, so I don't know what is going on but this is happening all the time now, and was just wandering if anyone can help because I am starting to get more frustrated the longer this goes on for?

Maybe she is concerned about getting pregnant.

Nah don't think so because she's on the jab so can't get pregnant and it was fine before up until about a year ago onwards

What's her side of the story, or have you ever asked?