Be business like in your interactions if you need to work out logistics of things. Also do not show any kind of emotions and do not let him use children as a gateway to get to you. Do not try to reason with him, or ask questions of why things happened, do not say I care about you or show him affection that he does not deserve. These things are all hard to do and DB is about doing things counterintuitively, a lot of us came here too late in the process and we made these mistakes because we all thought we could get through to them, or fix things. If you have feelings to share do not do it with him, a good therapist makes all the difference. You are taking baby steps but you have to detach more. I know its not easy but you didnt break this man and no excuse he uses is validx you cannot convince him to see the error in his ways. Seeing he might lose you and seeing you improve yourself is the only path forward for you. Do more activities with your children and work on your health and get out of your comfort zone.