When you're depressed, the last thing you want to see is happy people. They are infuriating and depressing. It is much better to see other people with problems, because it makes your own look less terrible in comparison, and because you're not an odd beast in their eyes, that one should pity or avoid as if you could be contagious. The problem, then, is not to stay locked in this circle forever.

It's like all the suicides in springtime: that's the time when the people and the nature are full of energy and joy and life and everything. And you are not, so the contrast is extremely painful and hopeless.