feel like a shitty fiancé

guys.... I’m seriously starting to hate myself. But everything I hate myself for just needs to be changed by me but it’s so hard to change so it makes me hate myself more.

i haven’t had sex with my fiancé in a month, maybe longer. I’m 19 weeks pregnant but I don’t think that’s even the reason why. Sex has always been an “issue” in our relationship because my sex drive is SO low. It’s never been important to me, I hardly ever want to have sex. But my man always wants to, obviously if I don’t want to then we don’t. But it’s selfish of me. Why can’t I just suck it up and do it. It’s gotten to the point where I’ve told him “I’m sorry I do realize how long it’s been but I’ll go back to normal tomorrow” then tomorrow comes and I don’t want to.

He used to complain a lot but it caused a lot of issues between us so now he just tries to understand and accept the fact that I never want to but he makes it clear that he wants to. I don’t know why I feel this way but it seriously makes me feel like the worst person to be in a relationship with. I feel like I don’t do anything right and it doesn’t matter how often he tells me he’s happy because I know there’s a lot about myself he wishes was different but he would never make me feel like shit about it and tell me. I really am being unfair to him and this may sound silly to most of you but if it was flipped and I wanted sex but he refused to give it to me for a month + then it would upset me. He proposed not that long ago and spent so much money on a weekend vacation for us and I didn’t even have sex with him then.