No sex drive whatsoever??

So I’m 28 weeks pregnant today and for the past couple of months I’ve js NO DESIRE to have sex whatsoever. My boyfriend and I have been together about a year and a half but still don’t live together (I’m almost 24 he’s 30) he hasn’t exactly stepped up since we found out we were expecting so idk if for some reason it’s cuz of my resentment towards him?? He makes promises to do things all the time and never sticks to his word.

Is it me taking my frustration out on him?? 😭