It doesn't surprise me this poor bloke suffered a breakdown. It only surprises me that more flight crew don't exhibit symptoms of psychological distress - or that they do but it simply goes unnoticed because a psychiatric evaluation isn't part of their regular medical check-up 'unless it is deemed necessary', by which time it's far too late.
I personally know another airline pilot who really shouldn't be flying, for psychological reasons. He's just gone through his last medical with flying colours, but he's as mad as a hatter, his private life is in shambles and he has expressed a 'premonition' that he will crash sometime in the next year. But what can you do? Airlines invest a lot of time and money in their pilots, and until the cracks in his psyche become too large to ignore, he'll continue to fly. I only hope that NOW airlines will start making psychological assessments as mandatory as eyesight and hearing tests. Believe me, there are other pilots flying who need help before they endanger passengers and themselves, not after.