I've never been diagnosed, but I know I have OCD. I've spent hours in a store, there only to buy a couple items, but I get crazy trying to reorganize their jewelry display by ring size and color, or books by author ("waah, who put Steven King next to W.E.B. Griffin?"), or sometimes just reorganizing items by size. Like the photo frames at Dollar Tree. I have a big problem walking by those.
I wish my OCD ran toward other things, like keeping my carpet vacuumed, or washing the dishes spotless. Sadly, I could not care less about those things. Meanwhile, my library is alphabetical by genre (fiction, non-fiction, with a separate category for novelized movies and Matt's huge Star Trek collection). My CDs are also by artist and genre (jazz, classical, modern, I don't go too crazy because of cross-genre artists), and my DVDs are alphabetized by title. I used to alphabetized my spices, but now I clump them by cuisine (Italian spices, Asian spices, Mexican spices, etc.) Maybe it's because I worked in the school library starting in 4th grade, but I'm obsessed with ABCs.
OCD and writing are a hard mix. Usually, I start with just writing. I get an idea, sometimes plot it out, often not, and GO! When I'm in that mode, I write, and I don't stop, not for food, not for sleep. I've gone for weeks on 3-hour naps because I'm up all night writing until I'm literally typing in my sleep (crazy weird crap written in the moments of fading consciousness) then jolt awake with a great idea and write some more... for 21 hours straight.
Editing gets fun with OCD. I've read that most writers hate editing their stories. They have this great tale, and they don't want to change it. Steven King suggests shelving new manuscripts for months. Yeah, I have to do that in the final stage, but I still go into a frenzy when I'm in "Edit Mode." I've been known to sporadically scrap a newly written manuscript and rewrite the whole thing, all because I came up with a great idea. Don't worry, I keep multiple drafts, because sometime my mania-driven "great idea" turns out to be really stupid.
I obsess over grammar, yet I speak with some Southern peculiarities. "It needed done" is my husband's favorite. I never catch them, not after years.
"Why did you rewrite this? It was a great chapter!"
"It needed fixed."
O.o "Do you mean... it needed to be fixed?"
>_< (grrr) "Yeah..." I also obsess over my character's names, often for stupid reasons. For example, in my manuscript Daughters of Ashby, all of the characters and place names are after trees, with a few shrubs thrown in because I liked the names. While some are obvious (Linden, Hazel, Willow, Mimosa, Palmetto), and others are not too hard to figure out (Olivetta, Betulla, Quennel, Garnock, Mandel, Avalbane, Feàrn, Verbina), some of my favorite names are really obscure... probably not even names for people (Serenoa, Catalpa, Quercus, Tilia, Cedrus, Zelkova, Quillaja). I did hours upon hours of research. In every edit, I change at least one person's name to fit a plant that better describes their personality. It's probably all a waste, but I find research fun. Why all trees? I have no frickin' idea. I needed a bunch of names, so I looked on some baby name website, searched for tree names, and from there it all went crazy. I can count on one hand how many things are not named after trees (one is a horse).
So what am I obsessing over now? Editing! (insert maniacal grin of impending doom) Adding chapters, removing chapters, rummaging through old manuscripts written from before I discovered that publishers don't want 300k-wordcount tomes and breaking them into trilogies. I'm currently working on what I guess will be the second book of the Blue Fire Dragon series (yes, series... sadly, it looks to be 7 books long, not at all what I wanted!) I'm bouncing every week or so between Daughters of Ashby, Blue Fire, Ghost Coast, and sometimes I try to add a page or two to my eternally-on-hiatus Shadowstrider, which must one day be faced with breaking it down to publishable size, as much as I hate doing that AGAIN!
I just can't keep on task. Sometimes I obsess over a story, sometimes I obsess over a process. I feel like I'm drifting aimlessly, but I know at least some work is getting done, even if it's in a discursive way.