So, what type of job he could apply?!
He's very young, there is a lot of pressure on young people nowadays. It's hard to start your own life, not even mentioning your love life.
If you find the right job and the right partner, it will help a lot not to feel so lost and depressed.
I agree with the others: you need to find an alternative for the drugs. However, I personally know people at my current company who takes or have taken antidepressants. Depression is very comman in this world, although, most of the people don't ask for help and don't get any treatment. I'm sure that there is more cabin crew struggling with depression than we are awere of...