I think he's cheating....

Our relationship started over a year ago. Before we where "stable" he kept jumping back and forth from me to another girl. In a way I knew I was the side Chick. He lied to me about being with her when he was with me. He told me they weren't together when they where. Anyways we stopped talking last year for a good 2 months than he came back into my life and we started dating but he was still getting over this same girl and going back to her to comfort her making calls to her all the way up till 4 months into our relationship. I never felt insure after he stopped talking to her things where good between us once he finally got over her but for the past few months he doesn't want sex, he verly touches me or talks to me, we have lost all connection, I'm 20 weeks pregnant, he's complsivley lieing to me about things like smoking, when he leaves work etc. I knew he has always been a compolsive liar but this is getting stupid bad. He lies to me about drinking, and what he is doing. Than he uses the remark do you seriously think I'm cheating on you which I reply yes. Change in body language, never home, lies alot, never let's me see his phone and Mt gut is saying RED FLAGS RED FLAGS but he always makes me feel so bad for thinking and asking if he is. He says it irritates him and it's bullshit. Etx. Am I crazy or do you think he is cheating. He even smells different when he comes home. And he doesn't pay any attention to me or the baby. We were meant to do all these things like photos nursery stuff and I was left to do it well he sits on the couch on his phone.