You need gradual exposure therapy. The only way to make it go away is to face your fears. I have written a book, Anxiety Protocol, that shows you how to make performance anxiety go away.
In the meantime, you can consider visiting with your doctor for a prescription of a beta blocker, such as propranolol. Propranolol can be taken on an as-needed basis, right before your performance, to decrease your anxiety about performing in front of people.
If you prefer a natural alternative, then the natural anxiety supplement, KalmPro, may be helpful.