Feeling lost

My relationship was amazing....I have two children from a previous marriage. He is great with them. I have come from a multitude of problem relationships where the men are unfaithful... It affects my feelings. He has become distant and we are having sex less and less he doesn't try to have sex with me any longer. I'm 15 weeks pregnant and feel lost and alone. I feel he no longer loves me but is tolerating me for some reason unbeknownst to me. I now cry every night I know that is likely hormones. That though feels like a heavy heart lost in the emptiness that he offers. I don't know what to do any longer I've attempted to talk to him about it and I get dusted off.