whats the answer to insecurity feelings

sometimes i have the realization that my elderly mum & dad won't be around forever, i'm exceptionally close to my mother as i always have been.....i have no other support mechanism, lost touch with old friends from the past and that one day, i'll be alone, deserted and abandoned - on my own in a horrible world.

i live alone right now as i have done for 19 years. and all this makes me feel insecure....i'm a lone male, 46 years old, help, what am i going to do?