Sexual attraction

So like any woman I love sex. But I have a few problems. The first is it tends to hurt a lot. It feels like there is a lot of friction which in return feels like burning and then I go numb and can’t feel anything. This happens often and it’s quite irritating. My other issue is that I don’t know if I am sexually attracted to my s/o. We have been together for over 2 years now and I like to have sex, sometimes though I would rather just rub one out then sleep with him. My boyfriend is very skinny and seems to only be getting skinnier despite his constant effort to put up weight (or so he says). But the fact that he is so skinny makes me feel sad and idk why. But as a result of this I don’t necessarily find him sexually attractive because of how skinny he is. I am wondering if anyone can please give me some advice on what I could do ?? Sometimes I feel like maybe I don’t have a sex drive but I don’t think that is the case I think I have a sex drive just maybe not for him? Please help !