When you just kind of give up and accept that aRTD is your ultimate comfort canon.
When you have over 15k total in the works for various WIPs, and more on the way.
...When you re-read part of it and find yourself identifying with Hannu more than you should, probably. (My inner Hannu-ness is very tightly restrained, I try not to inflict it on people ;V )
Everything is aRTD and nothing hurts. Bury me with this comic, honestly. Well, okay, one thing hurts, and it's the fact that I don't have the book, but I will endure.