Cheating What Should I Do....

My boyfriend who I’ve been with for two years and have a one month old babyboy with is cheating on me. I got into his phone and seen text messages with another girl. He hides his phone At night time and then puts it away till I’m around him. I caught him and he was apologizing like crazy finally i forgive him and i hacked it again and saw he changed the name to something else but i remember the #... what should i do? I’m hurting ...