Needy partner wants sex all the time

Hi, so I'm 18 weeks pregnant and in a good amount of pain 99% of the time. I have terrible migraines, I can't take my meds cause of being pregnant, my hips are so sore. I can't sleep because I can't take my meds and I'm slight insomniac. I still have morning sickness that hits randomly all day.. its been a rough pregnancy so far.. we also have 2 other children, one I'm trying to sleep train in his own bed.. its not going well..

My partner wants sex every night, but says he will accept every other night. I don't want to be touched let alone have sex. But I said I can suck it uo for once a week like Saturday that way we are both there for when the kids wake up and I can get a few hours of sleep and I can recover. He will not take that as an option so I get mad and say no sex at all.

I understand people have different sex drives and need more nut I feel like he's being completely unreasonable.. he even tries to guilt trip me by saying I don't love him. Am I wrong?? What can I say to get him to understand? I'm getting like mad mad..

Thank you in advance!