I can read the resolve in your last post. I am so sorry that your son sees this is a some sort of slight to his relationship with your AH. He can still do those things with him just from a safe distance. Do try to hold on to what you said about this being for the best. It is what it is and it has to be done to protect you and your children. You are falling off the face of the earth. You're just leaving the house and just as you can move out, you can move back in. Of course that is if, and only if, your AH gets his act together.
Try to take expectation of anything, good or bad, happening this evening. Any anxiety that you have over his coming home at the end of the day will only electrify the situation and possibly make something out of nothing.
You are taking this step by step, and each one in turn will get you out of this mess. Trying to jump ahead won't do it.
Hang in there!!
Alice