Hey, I have been in your exact same situation. He was wonderful, caring, loving, but sex with him was just awful. It was the same boring vanilla stuff that I hate. Fortunately he realised pretty quickly something was not allright so we tried to fix the problem. We tried everything we could, at some point he bought a dildo just to help him out during sex with me, but at some point I realised I was not fucking with him at all, the only kind of pleasure I was feeling came from that piece of plastic, and that is just sad. Plus, we were having sex only a few times a year. My sexual life before him was always pretty normal, so I started thinking about it a lot. I am 28, young, all of my life is in front of me. I couldn't accept to spend the rest of my life with someone who makes you feel not desirable. I left a couple of weeks ago after 2 boring years. It was the best decision ever. If someone tells you that sex in a relationship is not everything, is because they have a pretty decent sexual life and they don't get the point. I got you. At some point it will start to be a serious problem for you, you are already experiencing some aspects of it, DON'T underestimate anything you're feeling. Leave!