DH has OCD. It doesn't involve cleaning or putting things in order. It involves being so worried that he has forgotten to do something important, that he struggles to start any task, because then he'll be doing that, and might not manage to do that elusive, most important thing. We joke sometimes that he is like the sailor in the poem by AA Milne, but it is actually a really horrible and ifficult thing to struggle with, that constant nagging feeling that whatever you are trying to do is WRONG but you don't know what the right thing is.
The Old Sailor
by A.A. Milne
^There was once an old sailor my grandfather knew
Who had so many things which he wanted to do
That, whenever he thought it was time to begin,
He couldn't because of the state he was in.
He was shipwrecked, and lived on a island for weeks,
And he wanted a hat, and he wanted some breeks;
And he wanted some nets, or a line and some hooks
For the turtles and things which you read of in books.
And, thinking of this, he remembered a thing
Which he wanted (for water) and that was a spring;
And he thought that to talk to he'd look for, and keep
(If he found it) a goat, or some chickens and sheep.
Then, because of the weather, he wanted a hut
With a door (to come in by) which opened and shut
(With a jerk, which was useful if snakes were about),
And a very strong lock to keep savages out.
He began on the fish-hooks, and when he'd begun
He decided he couldn't because of the sun.
So he knew what he ought to begin with, and that
Was to find, or to make, a large sun-stopping hat.
He was making the hat with some leaves from a tree,
When he thought, "I'm as hot as a body can be,
And I've nothing to take for my terrible thirst;
So I'll look for a spring, and I'll look for it first."
Then he thought as he started, "Oh, dear and oh, dear!
I'll be lonely tomorrow with nobody here!"
So he made in his note-book a couple of notes:
"I must first find some chickens" and "No, I mean goats."
He had just seen a goat (which he knew by the shape)
When he thought, "But I must have boat for escape.
But a boat means a sail, which means needles and thread;
So I'd better sit down and make needles instead."
He began on a needle, but thought as he worked,
That, if this was an island where savages lurked,
Sitting safe in his hut he'd have nothing to fear,
Whereas now they might suddenly breathe in his ear!
So he thought of his hut ... and he thought of his boat,
And his hat and his breeks, and his chickens and goat,
And the hooks (for his food) and the spring (for his thirst) ...
But he never could think which he ought to do first.
And so in the end he did nothing at all,
But basked on the shingle wrapped up in a shawl.
And I think it was dreadful the way he behaved -
He did nothing but basking until he was saved!^