How to keep house while drowning by KC Davis: how it's not morally wrong to have a messy living space, and how to keep it livable even when you feel like you're overwhelmed.
I have ADHD and depression, this book was pivotal in helping me get out of the stereotypical "depression apartment" situation.
I was going to suggest The Hitchhiker's Guide to the Galaxy, after all, they will already have a towel.
As someone who used to troubleshoot an extremely complex system for my day job, I can say I've worked my way across the entire bell curve.
We met on OkCupid. We were on opposite sides of the Atlantic, but she had a friend on this side, and they were comparing the "weird" profiles they were each finding. OkCupid has a "if you liked this person, you might like these more" section, and I appeared in there. She wasn't really looking to date anyone, but she clicked, messaged me, and we clicked. I moved to the US to be with her after a two-year long distance relationship, and we'll be celebrating our ten year wedding anniversary next year.
It's definitely great in theory until you inherit a codebase with no tests, poor documentation, and numerous reported bugs already live in production. Even better if it was written by people hired because they could do other things better than they could code - which looking at some of the unlabeled wiring messes we were left, isn't saying a lot.
Tubular Bells, also known as the Theme from The Exorcist.