There are hundreds of variations of OCD -- basically, a variation for each thing you might have a fear over -- as fear and anxiety are at the root of the behavior associated with OCD. If you can fear it, you can probably create an obsession over it.
Much like the author, I also suffered a "nervous breakdown" in my 20s (and I'm still in my 20s, so this wasn't that long ago...) and tried to get myself hospitalized for the sake of my immediate family, as taking care of somebody in that state is emotionally exhausting. Fortunately, I had terrible insurance at the time that didn't allow for "non-critical" inpatient hospitalization, so I ended up going back home. This ended up being the right decision, because as mentioned in the article, exposure therapy is the best way to treat OCD. Avoidance behaviors actually _reinforce_ the damn thing, only making you worse.
I've thought about writing in more depth about my particular form of OCD, which is a difficult one to treat as my compulsions are entirely mental (compulsions are just reassurance seeking behavior, and you'd be surprised at the mental gymnastics one can try to jump through to reassure themselves about a situation). I consider myself very fortunate for having lived in a city with one of the best OCD clinics in the country, as I went through a few months of clinicians and psychiatrists not really understanding what was happening to me, before ending up at the right place.
Writing about OCD is incredibly exhausting, because as many other people have related in this thread, even reading about OCD tends to be triggering to sufferers. Writing about it is basically saying, "hey, I don't mind exposing myself to old and new anxieties over and over and over, with the potential to make my next few weeks miserable", so the people that do it are admirable. Probably healthier for it, too, given it's basically therapy.
I can't imagine what it's like to write a novel, like John Green did with Turtles All The Way Down, while also being a sufferer. I'm sure medication must help. ;)