I don't know. I'm not an expert.
Sometimes I'm just tempted to say it's all demonic in nature- ofc sticking to that dogmatically, I'd have to *mod edit* then eventually ban myself.....
But, just as it's sometimes handy to treat light/electricity as waves, and sometimes it's handy to treat is as particles, it's sometimes handy to see OCD as being something fundamentally wrong with your brain, it's wired wrong, it gets stuck in these loops, blah blah blah. And sometimes it's really, really handy to think of it as an outside force, a living thing that's got squatting rights in your head. An imp.
So.... yeah sure why not? Wolves target the weakest elk, right? So why not jump your ass when your resistance is lowered? Best time to do it. OCD for me is an imp that feeds on fear. It will do anything, ANYTHING, to create more fear.
And since the imp is you.... a real-world version of Doctor Morbius and his "
Monsters from the Id". It knows all your weaknesses. It knows how to get under your skin, it knows where to twist the knife.