WOW, your stbx sounds as manipulative as mine was. I hope the Judge is in your favor! Why were you both at your son's doctors appointment? There is no need for that in the future. You should not be in the same room as him when there is a possibility of him assaulting you again, and that is what he did. You are not his wife any more, and you need to set boundaries, and if he crosses them, take action. Start saying "No" and "Do not touch me". You had a protection order against him? How long for and when was it dropped?
No advice on how to get over your husband, it takes time, but you do have to adjust to the fact that he has no positive feelings towards you. To him, you sitting on his lap (even though you were unwilling, it was not with your consent) was proof that you do not fear him at all, so there is no reason for you to co-parent with maximum interaction. My ex pulled a similar stunt, asked for me to do a handover in McDonald's, knowing the kids would want to sit and eat, so I was with them when he arrived and didn't leave as soon as he arrived. He bought it up in court to demonstrate I was not scared of him. (I sat away from him, there were other people there, and interaction was tense. The Judge saw I was set up, she already had seen how deceptive my ex was. Do not put yourself in this position again!!! As someone else said, keep contact to a minimum, and only child related. No talking. Keeping contact to email is best, text if not. Email is good as you do not have to reply immediately and you can edit your writing. Keep writing factual and unemotional. He doesn't care how you feel and will use as much as possible against you. ( I learnt this the hard way.) If he tries to be with you without someone else being there to help you, try to get a security guard to accompany you. My attorney would make me wait 10 minutes after court would end, and escort me out of the building after checking he had left. Luckily for my, all of ex's attorney's (he got through 4 of them) helped as much as possible.
This is a wonderful forum to come to for help, support, advice and general chat. I hate to say it, but welcome! I'm glad you found it!
Are there any support groups for divorcees you could go to?