Sex more of it?

I'm 20 my fiancé is newly 22 and we've been together for just over 5 years. We started being intimate about 2 years ago and were just not sexually conpatible . It's quite frustrating. I have a much higher libido than he does. We've tried introducing newer (kinkier) things but nothing works it's a hassle to get him in the mood and when it's forced it isn't particularly pleasurable for either of us. We get maybe one amazing ... Like toe curling ... Yes... Sex session a month if I'm lucky. I don't know what to do it's absolutely maddening cause I have tried  mastubation  and it doesn't work for me at all...help ?