xtreee: I'm sorry you feel like giving up in therapy. You said you tried writing, but it didn't seem to work. Did you try what Dani suggested, just writing down the topics, and then letting your T take the lead? Does your T ask questions, or just wait for you to say something? Can you get T to ask you if he/she doesn't? Will you answer them, or you just don't want to say anything?
I can relate to this because I used to have trouble talking to my first T. I would sit there for a long time not talking. Can you talk about non-personal things with T? Have you tried that in the beginning of the session? I also think your T should play a more active role if you have trouble talking, and wonder why he/she isn't doing this, or if it hasn't helped.
Don't give up! Maybe a different T who knows your difficulties would be able to help you open up. Do you see a pdoc too? Is there some medical reason for your inability to get hold of your thoughts, maybe?
One more idea. What about talking into a tape recorder, or is that worse than writing? I once did that for myself, and I was surprised at what I had to say. Usually I'm more open in writing.
I'm sorry you're sad. Don't give up!