Feeling unattractive and unwanted while pregnant

I’m pregnant and feel like I’m not attractive anymore. My boyfriend would rather watch porn and jack off than sleep with me and it really upsets me. He knows I don’t like it and says if I complain about it he gets to have a threesome with me and another girl (long story about how that came to be a thing). That’s not how it works. Then a week or two ago I had a girl message me on Facebook saying he had messaged her asking to hook up. He even told her he was with me when he asked her. Luckily she had my back and told me, she was super nice about it. He was trying to cheat on me. This happened literally DAYS after he had asked me to be his girlfriend again (we had previously broken up, he started talking to other girls instantly but still hung out with me because I’m pregnant with his kid and he says he loves me, and then he asked me out again). I confronted him about it and he said it would never happen again and deleted his Facebook. But since then I’ve felt even more sad and unwanted and unattractive.

I’m not looking for any one to say “break up with him!”, I want to be with him. But I don’t know how to get him to realize how all this makes me feel. And it helps to vent. He used to come to therapy with me but now he doesn’t. It makes it hard to talk to him about my feelings because I feel like he doesn’t consider just how bad it really makes me feel and what’s been going on in my head due to all of this.