I know how you feel because that is the way my xh was, i.e., so detached it wasn't funny. You have to remember that they detached a long time ago, i.e., long before the bomb drop So, he's ahead of you by a few months. It's going to take you awhile to detach more...but I know you can do this.

I wasn't surprised that he had nothing to say and appeared not to have read it. Their minds are a jumbled mess and they truly cannot focus on any one thing for very long. When something comes along to distract them, well....the important stuff then sits.

Let's face it, he's an emotional mess right now and it's going to be many months before he can get it together. I would continue to move forward and if he truly has something to say about the separation agreement, he will come forward. Do what you need to do and do not allow him to drag you down.

Sit quietly, the answers will reveal themselves when you least expect them to.
The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.