I HATE HIM TODAY 😢😭😭😭

I'm totally in my feelings today, my thoughts are killing me. I've been in deep thoughts about how I'm going to end up doing this alone; I say this because for some reason when you get pregnant, your man does unlimited stupid shit. Yesterday his ex pulled up screaming that they are still having sex after a year of being apart. He completely denied it, saying she's just mad that im pregnant, she showed me a few text that she MADE UP (pics of them together) she used some type of app. I know they are fake text because the dates that she choose to use are a few days that we were together for Memphis in May. My question is why tho, why did she really do it. We've been together strong w/o any drama since forever he comes home every night, answers all my calls, takes me out, pays the bills, brags about me and shows me love like no other and I'm greatful but this incident has gotten the best of me. I don't know who to believe, I think I'm going crazy, I'm scared because I just went through a divorce of 14yrz last year, lost a lot of weight, got my body right, bought myself a BMW truck, met him and we fail in love. Now I'm pregnant and feeling stuck TEARS