I write angsty stories, but my characters are not depressed. They're living their lives but know that particular aspects of their lives are not perfect and need work. They're not ranters and don't use the absolutist terms the article cites.
Years ago I used to love reading about incredibly put-upon heroines who had every right to be depressed by their life circumstances. They often were beaten down (metaphorically) by mentally ill, selfish, or nasty relatives or bosses, or by extreme poverty yet the insistence of all around that they keep up genteel appearances. The heroines also tended to get trapped into a very British-oriented situation of having too much pride to ask anyone for help and having too much duty to family to confront a family member causing the trouble or justify to an outsider why the heroine herself is not guilty of the bad thing another family member did. Talk about depressing. But these heroines were not depressed. If anything, they were plucky. Everything in the story from then on might seem to get worse, but the heroines got stronger and more determined, even when they got more miserable because of those heavy-handed (in more ways than one) Harlequin "heroes." And eventually, these heroines triumphed (or thought they did; a revisionist exegesis of some stories would say otherwise).
Heroines who start off depressed because their lives are empty and they don't know how to change anything are a bore to read about. I've come across a number of mss. that started that way (and seemed to include a lot of coffee drinking and cats). They're never interesting. It's important to make sure your lead character has more strength of purpose than the average person and is not self-isolating. True depression makes the world all gray.
As for putting clinically depressed characters to a story, unless you're writing an epic or a saga, there isn't enough time in the course of a standard modern novel to show how someone genuinely depressed typically does slowly come out of it. And since the suicide rate goes up as people get slightly less depressed (still depressed, but meds or therapy have given them more ability to act), it's quite dangerous to write about depressed characters in the short term. As for self-abuse addictions such as cutting (I should research this), I suppose it's possible that the unhappy high school girl goes to a great college and gets a wonderful roommate and a brand new circle of friends instantly and simply drops it off. But I wonder if that's how people stop.