Pregnancy sex

I’m 26 weeks pregnant, in my first trimester I hardly wanted to be touched- let alone have sex. I felt sick and achey all of the time. Fast forward, I’m nearing my third trimester. The past few weeks I’ve really started to show and it’s made me a bit insecure as I’ve always had a tiny build and every time I see someone I know I hear “oh my god you’re so huge.” I know my partner loves me very much and is excited for the future together, I have one problem currently though. He just doesn’t really initiate sex anymore. And I know me feeling insecure is probably playing a bit into me noticing it, but he openly told me he jerks off in the shower when I’m home sometimes and it has really been hurting my feelings. My drive has shot up and that combined with the random insecurities I’ve been feeling are creating a clusterfuck of anxieties and overthinking. I guess I just want to feel desired, especially now that I’m feeling a bit undesirable. I talked to him about it earlier last week, then got upset when he jerked off in the shower after I’d expressed my sex drive increasing. He said he’s tired from works and sometimes just wants to relax in the shower alone; and that he just doesn’t always want to have sex. (All understandable.)

Disclaimer: Loyalty is something we are both very serious about, I don’t think he’s doing anything hurtful/dishonest/being unfaithful.

Can I please get a guys perspective on this. I feel like i may have kind of ruined the intimacy by not wanting sex for a while as I was very frequently nauseous/achey.