I vote long life with dignity. 
I had a friend who was diagnosed with a brain tumor in his early thirties. They didn't think he'd make it six months. At his 40th birthday party, I sat there thinking that I'd never look at milestone birthdays the same way again.
We lost him a couple of years later. Life is too precious to not celebrate every day of it. If you're starting to go "over the hill" grab a sled and enjoy the ride!
"...for the happy heart, life is a continual feast. Better to have little, with fear for the Lord, than to have great treasure and inner turmoil." Proverbs 15:15b-16 NLT
The pessimist sees difficulty in every opportunity. The optimist sees the opportunity in every difficulty.--Winston Churchill