Do you want to have a relationship long term with this person? Was he always this way? Maybe he doesn't want to admit that sex with a preggo makes him uncomfortable? If you don't want go ruin your relationship is say get your masterbation on! If you think you're always going to be frustrated with him and you're never going to feel fulfilled and happy, you might need a relationship status change. Give that decision a lot of careful consideration though since it effects two others lives as well. Good luck. Ask himto try enhancement products??
I know your situation is tough but have you considered that perhaps he has a problem. Erectile dysfunction is a possibility. Maybe you should try to sit him down and have a serious conversation. Try not to put him down or make him feel bad about it but if you voice your concerns, he may be willing to see a dr. There might be a easy fix with medication, leading to a much happier life for both of you.
I am in a similar situation, I want sex often but when he wasn't on the same page I talked to him and told him that I needed more affection and I felt he didn't want me like before, and he told me that he honestly feels uncomfortable having sex too often because of the baby. He feels dirty almost. I understand that completely and have slowed down a bit, but now we have both compromised and things are better in that department. I never wantedto cheat(except maybe with myself, lol!) So it sounds like there is more to it than just that. I know that no matter what I love him and I want this baby to grow up with him, and I wouldn't do anything to change that. Every relationship is different and I'm not judging, but it sounds like you need to have a talk with him and be honest about feeling neglected in that aspect.
I have but he doesn't understand me, he says it shouldn't be when I want it but when he wants it. Which is never, and he says that I'm too demanding. I've tried to talk to him but his understanding isn't right, he's just crazy. When talking to him he likes to get loud and upset even though I'm not yelling. So yeah I really hate to say this but he might just not be the one for me.
And every one else that views the situation says he might just be gay...
And I don't think Ed is the issue he can get aroused and continue doing sex. He just doesn't like to have sex like a normal person.