Most people don't want to live to be that old, most likely because who do they have? All of their children are gone, (not many parents want to out live their kids), all of their blood relatives are also gone, all your friends are gone. Your alone. Too old to go out and make new friends or even do anything with out help. You have nothing in common with any one that is even 80 years old. I know that I wouldn't want to be alone and have people taking care of me and then one day they are gone and some one new is taking care of me.
The only thing that you have is "History" you have seen and been around things that no one else has. 120 is a great age to write a history book.
Stop by Phyl's Potpourri and visit