I’m feeling unhappy and empty in my engagement what should I do? Me [21m) her (23f)

We’ve been together coming up on 4 years now. Our sex life id essentially dead, maybe once or twice a month. She is (actually) sick or not feeling well all the time and tired at all times. She is a preme and had severe health issues when she was about 17 but that didn’t stop her from being fun and adventuring person after her recovery. When I met her when I was 17 and she was 19 it was mother most incredible thing I’ve ever felt. True addiction to her. I was leaving for the military and dealing with a lot of severe trauma from my parents and childhood, and she was there and being a sex symbol of a lover. Once while I was in the military I had talked to another woman and received nudes from her. She found them. I did everything in my power to make things right. After what I thought was a good healling period, I proposed. Not in a way I’m proud of, I was 18 and so excited and stupid and she was visiting me while I was on base, I did it in our hotel room. She said yes and she was so happy, fast forward one year I get out of the military. I move in with her and her mom. I pay them out of debt, pay their whole rent, fix the whole house. Now another 2 years later and essentially all sex stopped when I moved in and now we have the house and have for a year to ourselves, no people no kids, no sex. I a sexual demon and now I’m dying and don’t know what to do. (Also I’m drunk, please be kind about the shit time line)