Yes, actually i have had this problem... i don't even know how to explain how i got over it. I would try to talk to someone, a friend usually about things that have gone on in my life, and i just couldn't get myself to say what it was that was going on in my mind. The only way i can describe getting over it, was just to take a deep breath, forget about the emotional attatchment to what i was saying, and say it as if it were everyday speech. It would take me a few, or more than a few minutes to be able to do this, but it helped. I don't know if that will help at all for you, but its the only thing i can think of. I hope everything works out for you.
~Julie

"Sometimes it takes us to the bottom of our misery to understand the truth..."
~Gustav Havel - existentialist