Hi Phyllis. Sorry you're still having this awful problem.
I also suffer from terrible anxiety from time to time, but nothing about death and dying fortunately. (except that sometimes when I have a panic attack it feels as if I'm dying!).

Have you ever looked at some of the articles about your fears over at PsychCentral? There are some specific articles pertaining to your fears.

e.g.
http://blogs.psychcentral.com/therap...e-therapeutic/
“No Leave, No Life.” Can Death Anxiety be Therapeutic?
By Gabrielle Gawne-Kelnar

http://knol.google.com/k/anxiety-and-panic#

http://psychcentral.com/disorders/anxiety/panic.html

There are more... just type in a search engine something like "Psych Central Anxiety about dying" or similar words.

There are also some excellent resources in the Sticky post at the top of the messages here.
http://neurotalk.psychcentral.com/thread1395.html
Useful Websites and Resources for Anxiety & OCD