Sex/masterbation

My sex life with my husband has been kinda dead lately. I'm pregnant and by the time he gets home from work I just don't feel in the mood. I think part of it is I don't initiate it at all. I do use a vibrator while he's at work sometimes and it's just easier and almost better than sex. When he's inside of me now I feel so much tighter its kind of uncomfortable and I can feel my uterus moving. Does anyone else have this problem? I don't know how to get back into it with him! I'm ready for bed right after dinner at like 8pm and just am not horny at all.