personal fears and career

[private]

This is a non technical question.  I am guessing most of us here are
interested in extending our own personal lifespans.  I still have a
nagging doubt about going into this field for my own personal reasons.
I still don't know how to answer the criticisms such as why do you
want to live forever, you don't really want to live forever, etc.  Is
my fear of death a justifiable reason to choose this field as my
career?  What do I say to people who suggest that I need to get over
my fear of death instead?