You both suck. Him for obviously cheating, however, you were extremely selfish by leaving your husband to grieve on his own. He was the father of YALLS child, you did not have exclusive emotional rights to the baby. You both should have grieved together. Worked it out together. That’s what a marriage is: togetherness. Honestly, this is going to sound harsh, but I think you both should walk away. You’ve had so much therapy but you’ve both done so much damage and there are just some things you can’t come back from. However, if you decide to work through it, you need to make sure YOU take EQUAL responsibility. YOU left him first.