I have a 45 year old brother whom I believe has a type of OCD. The most glaring example that convinces me of this is his almost incessant counting of his money.
He often counts his money in one instance and a few minutes later, without spending it or taking it out in the interval, he'll count it again. It's as if he doubts his own memory.
When he was younger he used recreational drugs and this behavior was worse. He'd ask me a simple question and I'd answer it then moments later he'd ask the very same question again. I'm sure it wasn't just bad memory because I'd get pissed at him and make him repeat the answer I'd just given him. Again, it seemed like he doubted his own memory.
Is this what OCD is? The inability to trust one's memory?