What could a mother do for a depressed son?

Ok Listen to this. This is NOT about ME!!! It is for a book I am wright and would like a little help with a question I am stuck on! so please DO NOT think this is real. thank you.

What would a boy (age 14) who with his girlfriend (age 14) and two best friends (16 and one 17) went to a party. The girls got REALLY drunk and he wasnt that bad. He thought it would be better for him to drive and he had a bit of driving expericne. well during the drive home things where fine. intell the 17 year old went and pushed the boy to look at something. being dead drunk she didnt fully relized that was a bad idea. he lost contrle of the car. (the road was wet and some glass was brocken on it making the tire flat) At the same time a car came and crashed into them. Well the car went over the bridge they where on. they all got out but the boys girlfriend. he tried to save her but was unable to. she died that night but the boy didnt go to jail nither did the girls. the drunk man who hit the kids was sent to jail and the three teens had to do compuity work. The boy took it the wrong way and blamed in on himself. He was head over heels for the girl who died. he stopped talking and never smiled and never laughed for a little over a year… what I need to know is what the mother could all do. I though about therpy but he wouldnt talk so im not to sure what his mother could do. If you could help me it would be much appresated. and once again this is not real. its for a book. thank you.