Here's the thing- you can't take it too personally from the perspective that he did it w/o consulting you...this is b/c in his mind he may be done anyway- for whatever reason.
Good 180's are like what you did- being somewhat supportive and not beating him up over it...had you completely gone off on him he may have set you both up to where he can justify his intentions of leaving.
That doesn't make it right...it is a burden on the family and it was a rash decision...can you deal w/ that?
Also remember WAH is not H- he's in selfish and impulsive mode...again no excuse, but can you deal w/ that...for now?
If the answer is No, then you know what to do...i the answer is yes, you know what to do...