I have the same problem of not being able to carry a conversation, but lately it hasn't been so bad. All I can really say is, practice makes perfect. Every time you have a conversation, you'll get just a little bit better at it. Eventually you'll be back to normal. It's hard to take the first step, but it's just something you have to do, and you won't regret it. Eh, someone else will probably come in and explain it better than I can.