45 year old women , sex for 25 years

please help i\\\'am a 45 yearold women been having sex for about 25years now and i have had sex with eight men and sex do not feel good at all. i dont feel pleasure never. no orgasm nothing not even oral sex make me feel good could there be something blocking my g spot. is there such a thing i have now been with the same men for 16 years and have not had a orgasm but he dont know that.i want to feel pleasure down there. there is something wrong thanks