livid!!!

Ladies I'm really torn and heart broken I have no idea what to do right now considering our baby just turned 1 month old yesterday!  I found this on my SO phone monday night and I'm just completely destroyed inside.  Now he put a passcode on his phone and I'm livid about it like now I feel like he is hiding something.  I just feel like I'm not good enough because I've always had to compete with this girl and I really thought his son would make him a little different but I guess I was wrong 😢😭 I don't want my little boy to grow up in a broken home but idk how much more of this I can put up with 😕 what should I do ladies??