I was in the same boat, obsessing about my spouse's actions. My therapist taught me how to manage the anxiety. Her message was to focus on healing, first, dealing with him later.
If it hurts to talk to him, send an email. If he only communicates through your lawyer, do the same. Lay people don't do well against attorneys.
If a spouse leaves their spouse but stays a part of the children's life, it's because of dissatisfaction with the marriage. If the spouse walks away from everything, I was told it's a midlife crisis, which is said to last 2 years from the time of revelation, usually an affair.
Look at the facts. He intentionally has cut off all contact with you and barely any with his daughter, is inconsistent with taking his medications.
This is a time to GAL. Turn the focus on what you can control, your life, caring for your daughter. Deal with your husband without explanations points. Take deep breaths and relax. Let him come to you.. it's his choice either way.
I used to have 'no spouse days' where I would intentionally not talk about him. They felt great. When I did have to deal with him, once I was done, I'd send him blessings. It helped ease the anger.
Learn to define boundaries. Have you therapist help you. Counseling and medication work for you. You want to be in a good place to make good decisions.
Parameters I use are:
If it feels right, the answer is yes. If it feels wrong, the answer is no. If you can't make a decisions or keep waffling, the answer is no.
Along with "What is best for my child is best for me."
