No sex drive/painful sex?

I've been with my boyfriend for a little over two years now, and we have a fantastic relationship! However, it seems like I'm never in the mood for sex, we only end up having it around twice a month. I have heavy depression and anxiety and I am on Welbutrin, but it seems like such a process to have sex, get clean, and be exhausted after. Whatever we do have sex, it's incredibly painful for me! Much like the feeling of losing your virginity. He's of average size, we've used lube and lots of foreplay, but it seems to always hurt and I can never stay wet! I think i don't want to have sex often because it's rarely a pleasant experience for me. Help?