Great post, and I'm glad you're no longer struggling with that issue.

Growing up in a family where around half of the people had OCD, I've seen some very bad interactions with religion. I think that their particular brand of literalist Protestantism and their constant focus on the worst case scenario/worst possible interpretation were an inescapably bad combination. One relative is nearing 90 and literally spends all but 2 hours a night in prayer (no idea how she's kept this up for 40 years), and it's absolutely heartbreaking.

As for my own experience, I only exhibited OCD behavior in relation to religion as a child — I was unaware of my family's issues with religion, although I knew about other OCD behaviors, which I did not mimic. However, even though I wouldn't say that I ever really believed (my "official" deconversion was in 2nd grade), I still spent all my time trying to silently pray myself out of hell in some twisted version of Pascal's Wager. I've never had any other tendencies towards OCD behavior, and I stopped as soon as I stopped believing in hell. So, I would argue that religion is powerful enough to trigger obsessive behaviors, when other things might not — the stakes of eternal hell are a lot higher than leaving your car door unlocked, after all.

I do think that a form of Christianity that had a more structured/guided system of interpretation or even just more of a focus on education would be far less likely to lead to these issues. I'm long past my angry atheist phase and really enjoy studying Christianity, but getting a family member to watch a lecture from Yale Divinity School with me or read a book from a Bible scholar is literally impossible.

TL;DR Encouraging people who obsessively worry to interpret the Bible with nothing but a copy of John Hagee's Jerusalem Countdown and the Passion of the Christ on VHS will never end well.