I was notoriously quiet at school. And I never spoke to anyone when I went to Uni, and had real problems doing presentations etc. For a while I got so bad I could barely speak if I went out to get messages, would never do anything different or out of my routine just to avoid different situations.

The solution: stop caring. Also, if you fake confidence, you will start to feel it. There was an article on the BBC about how just adopting a more confident posture makes people behave more confidently.

These problems aren't trivial they can really change your whole view on life. Up until recently, my whole life I had a really negative attitude and just had this idea that everything was going to get progressively worse. It was depressing, its like having a physical weight pressing down on your brain. Probably tied to my OCD which was really crippling for a while.

But as I said, just stop caring. That is how to get over OCD or the problems like the OP. Going to be in contact with germs? Well you might get ill, its not that bad, no need to wash your hands 16 times at once. Going to mess up when you talk to someone? Who cares... its character building and if you make them feel awkward you can laugh about it to yourself.

That is why these days even though I'm sick of work, sick of Uni and don't really have any friends, I wake up feeling positive and like I can do anything I want.

Find something you like about yourself thats related to talking and will boost your confidence. For example, I have a pretty rough accent due to my dad coming from up north, sounds way better than the nasal whine most people have round here. I heard myself on a recorded phone message the other day and I have to say my accent is pretty awesome, I would't mess with someone that sounded like that, I sound about 20 years older than I thought I did.