Husband won’t have sex with me

I’m 24 weeks pregnant, I’ve stayed active throughout my pregnancy and so far have only gained 8 lb. I am definitely showing, but I’m not huge. And yet, my husband is just not sexually attracted to me. We haven’t had sex in weeks, despite the fact I very much want to. We tried having sex last night and he couldn’t “perform.” He said knowing the baby is there weirds him out. He also tried saying his sex drive is low, but when I asked him if he masturbates he said “sometimes.” So it’s not like he has no sex drive or that he can’t perform - I apparently just don’t do it for him. I feel so incredibly insecure, unsexy, and undesired. I’m trying to focus on the baby and be grateful I’m healthy and she’s healthy, but I’m really struggling with my self-esteem.