okay this is very familiar..... and I remember what my shrink said to me (or at least close to what she said)....

1) What is the WORST that can happen. Literally - write it out.
2) How likely is that to happen?
3) Have you ever experienced any challenge similar to this before? If so - how did it turn out.

The more you dialetically (?sp) process exactly what your challenge is - the more likely you will see that you can handle it.