As mamyalynne says, help your son to grieve and then try to educate him about MD. I know all too much about it. My ex-husband, who became abusive and threatened to kill me when I lived in France, tried to commit suicide when I eventually ran away (overdosing and alcohol) but was saved by a neighbour. 6 weeks in a mental hospital followed and the suspicions of our doctor were confirmed in that he was MD. There is very little, if anything, that any individual can do to help someone in the 'down' phase. Medication is needed and your son must not blame himself. If you put factual material in front of him this may help, once you have helped him over the first shock. You, and he, have my deep sympathy. x