Painful sex:TMI

I have always had extremely painful sex, I'm 26 and still have limited positions I can have sex in, I can't get on top or I will bleed, I have even passed out from sex before, I'm in the process of being checked for various diseases and syndromes including pcos  but my appointments not till next Tuesday, my current boyfriend is kind of amazing, he has always been extremely patient with what I call a" broken vagina" and says too tight is not something to complain about. Since I have been with him it doesn't hurt, we have a very healthy active sex life and we both enjoy it, but the last few weeks we have gone back to how it used to be, he has to go in very slowly and only certain positions and it's painful. Does anyone know how I can 1 stretch out just a little bit, 2 prevent this from happening over and over again. I have never orgasmed from sex ever one time