Yes, they do tend to go from being unhappy one month and on and on and on. If he had been that unhappy for that many years, he would have done something about it when it began to go down hill for him. You most certainly would have picked up on his unhappiness that long ago. It's the depression talking.
As for taking care of his parents...well, that may be true, but I suspect he wants attention and empathy. He is no where close to wanting to take care of his parents. He is still rambling on about things, i.e., wants the divorce yesterday, but can't get himself to hearings, etc.
As for you keeping the money and using some of it towards a vehicle for your son...that makes him look like an upstanding father by saying do it. The man is thirsting for recognition and an "attaboy" on the back.
Tomorrow...who knows...he could bounce back into another world entirely.
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.
