I’m really hurting right now

My significant other told some woman over Snapchat that he was still with me but he doesn’t know what my”true intentions” are since we had a baby. I’ve caught him multiple times entertaining other females. He was All over me yesterday and he’s constantly telling me he loves me and doesn’t want anyone else. Our baby is 7 months. We’ve been together almost 3 years and I’ve never given him a reason to not trust me. I don’t understand… if I bring it up to him he will just turn it on me and yell at me for going through his phone. I know I shouldn’t go through it but I’m tired of worrying about another female. Even if they are states away. Some are in the same city… I just am feeling like I’m not good enough. Why am I not enough that he feels the need to talk to other girls ?