I just need to talk about it

My boyfriend and I have been together for a couple years now. Our sex life used to be great. Like we used to do it every chance we got and now its maybe once a week. I know that the sex life of a relationship can dwindle as time goes on, but I also know that I'm part of the problem. I've had some issues in the past year that causes me pain when I have sex, which of course affects my sex drive. I used to want it all the time, but now I do it mostly because it makes him happy. Lube helps make the pain less intense, but it still hurts. I'm writing this post because I'm frustrated about how during the rare times in which I don't feel pain during sex, my boyfriend finishes in 15 minutes or less. At first I didn't care that he finishes so quickly because it happens sometimes(he can lasts for hours sometimes), but last night we were having great sex. For the first time in a long time it didn't hurt and I was actually enjoying it. He was hitting all the right spots and I wanted to finish so bad. I haven't had an orgasm in months, but after going at it for maybe 15-20 mins he finished. I'm not blaming him and I'm not mad at him at all, he was ashamed and embarrassed about it, but after I told him that he shouldn't feel ashamed, I went to the bathroom to clean up and just cried. I wanted so badly to have long, hot, not painful sex like we used to and all I got was 15 mins of pleasure. My sex drive is pretty much on E all the time and last night I was actually in the mood and I wanted it so bad. I feel frustrated and sad and I feel ashamed about myself because I know that sex isn't as good as it used to be for him either so I cried and then plastered a smile on my face when I left the bathroom because I can't tell my boyfriend all this, he would feel absolutely awful and hate himself.

I just needed to tell someone and get this off my chest.