I would agree that he is depressed.He is not happy with his job, with the degree he is working on. I've even talked to him about this but he feels he will figure it out himself.
Typical "guy" response. We all think we can fix ourselves. We all think we can do it without help. And we all are oblivious to the trail of wreckage we leave in our wake due to our inability to realize just how serious it is.
