[21 M] girlfriend no longer wants to have sex

I sincerely appreciate anyone who reads this post and offers advice.

I’ve been dating my girlfriend for 3 years. We are both Mormon. When we first started dating we had sex everyday, multiple times a day. Overtime her faith in religion has strengthened. I have always had a raging sex drive. Recently it has further increased because of anabolic steroids prescribed by the doctor. It seems almost impossible to refrain from sex and it doesn’t help that I’ve started to pick up an old habit of watching porn. I was addicted to porn for 10 years and I feel like I’m at the peak of my addiction again because it’s the only form of sexual interaction available to me at the moment. I recently confessed my addiction to my girlfriend and it broke her trust. I’ve explained how my sex drive is through the roof but I still want to respect her decision to hold off until marriage to continue having sex. I can see myself spending the rest of my life with this girl but I’ve had urges to talk to other girls and watch porn but I’m trying my hardest to stop doing that. It’s hard when I’m horny all the time and she doesn’t want me engaging in masturbation or watching porn. I’ve tried channeling my sexual energy to productive activities but any little trigger such as seeing an attractive girl at the gym or seeing a girl on instagram makes me incredibly horny. How can I navigate these emotions while respecting my girlfriend’s wishes?