My man watching porn/ no sex😔

My boyfriend and I broke up for 6 months a while back and I had been with someone else during that time. When we got back together he found out about that relationship and was devastated. He would still have sex with me often but two months after, it stopped .. like once every two weeks - once a month stopped .. one of those months I happened to get pregnant. I am about 4 months and through those months we've had sex twice. He tells me he thinks about me being with someone else and it hurts him so he can't have sex with me the way he used to. He also tries to blame it on the baby and me being pregnant. I would try sending him pictures, no acknowledgment. A few days ago I opened his phone and porn came up he had been searching a specific porn star as well.. I feel so hurt and I get horny so often I don't even know what to do. I try talking to him about it but nothing helps and he always acts victimized. Is it my fault ?