This is very hard, because it sounds like you still really love your husband. A helpful strategy is to put the emotions in a box and think of the situation as strictly business. This will help you analyze the situation and get through the divorce for your own sake and that of your children - it is important that you stick up for them and not let them feel that is is OK for their father to keep walking in and out of their lives. They feel like it's their fault no matter what. Protect them and protect yourself. You can take the emotions out later in therapy but don't let him get to you. Best of luck