What to do

For the pass couple of months I've been feeling like when I have sex with my fiancé after Wer done I feel like a prostitute. It has come to the point that I don't even enjoy it.. What can I do ? 😟 he even told me that if he cheats on me is gonna be because I don't give him any.. So should I just have sex with him so he won't or wt😔😕