26M in a relationship since 8 year, No sex life

Dear women Please advice!
I have been in a relationship since school and been 8 years now, I learned about sec when I was 13-15, Always wanted to have it wild, All in and with great intimacy, But with me partner I had it like 3 times in total, that too in dark nights as she’s shy! I feel m never going to be 26 again, Once i get married m going to be committed to this women and I’ll never have sex or intimacy the way i want it!

I do have want to explore a lot of things but my partner just doesn’t !

Should I look for sex out of my relationship before I get married, I know this would be considered cheating but you have enough context now!