Mine kept pushing me to get the separation contract done. I walked through the terms and told him what I was having written out. He freaked out and said, "this isn't the divorce is it?" I too was shocked by that, you are out of the house, sleeping with some whorish woman and suddenly concerned that it is the divorce? A year later, another woman, no separation contract (not even a single comment on the draft I sent 6 months ago) and no divorce filing (I check the county records).
You do need to mentally let go and stop hoping that he will come back. You do not have to answer his questions.
Very likely he was trying to find out if you were filing. They will often lie.
You really can do this. You need to believe this. And very likely the universe has something great for you when you are ready for it.
