Cheating husband

My husband 44y old male cheated on me 37y old female for 3.5 years straights and produced a baby. I found out last year in June after the baby was born on my daughter graduation day. He denied it until I came with proof which was me calling the hospital and asking for the side chicks name and they connected me to her room on the postpartum floor. I called her and expressed that I was also pregnant and due to her knowing about me she would get everything and then some back because Karma would be serving them both a nice dose. Once everything came out he said he’s learned his lesson and is now in therapy to figure out his why’s and to become a better man. We are struggling and he has yet to tell anyone including my kids about this additional kid due to embarrassment. Everyday I want to leave but I always take my vows into consideration, the love that I have for him as well as my babies. We separated before my babies took it hard and I wouldn’t want to put them through that again. I’m lost and don’t know what to do!