Asking him the questions...I have to agree w/mrsrjd, your chances of winning the lotto are very nil. They can't answer you w/a rational answer. In many cases the "I don't know" will pop out. I will advise readers of this, if you don't want to know the answer to that all time killing question, then don't ask. You just might get an answer that you didn't want to hear.
Congratulations to your son on getting his license! Woo hoo!
I'm glad you followed his lead when it came to the conversation and selected a different venue for dinner. The next event is the tree and then the party. It will be interesting to see how he reacts to both of those events because they should be happy and merry times. Life isn't good to mlcers when holidays come around...because happy memories remind them of what they had all along and now they are re-evaluating their lives. He will rewrite history to convince himself that his right to think the way he does.
Hang in there. I'm glad you are okay today.
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.