caught him cheating??

So I've been with my Bf for a while now since June 2016 but been on & off 2 times because he has a kid with his ex, which I didn't mind when I met him, I told him I'd accept him and his daugther as well. The only thing was his ex caused so many baby mama drama and won't let him see his kid, but this was going on even way before me and him been togther she don't let him see his kid only when she wants to, he's not allowed to bring his daugther around his family and what not. We broke up around September because he went back to her... and he came back around October 15 begging me saying he fucked up he was playing his cards to see his baby.. I accepted his apology, then in December we started TTC for our own baby... yesterday feb 1. She goes and texted him saying the mom & little girl emoji ( 👩‍👧) and I told him what's going on he said just leave it I don't want drama. And I replied back saying he only cares about his daugther so please stop including yourself he's with me. She then send me screenshot of him making an instgram behind my back telling her he wants to be back with her and he loves her and what not...  I packed my things and left. He was texting me after that he loves me and he just fucked up and to tell him what to do for me to give him another chance and get back.. it's been so hard, I left my parents house to be with him, accepted his flaws, his daugther and what not... I need some advice...