There's the advancing knowledge curve; advancing technology curve; advancing control of nature curve. In a hundred years or less those inter-linked accelerating curves mean business will be able to re-create an indistinguishable copy of any person -- complete with memories and sense of self--"I-ness". Forever.
Forever is a very long time. I can believe that one of my backup duplicates will be able to take over where I left off when the private space yacht fell into the sun, or was obliterated by a stray mini-black hole or an unexpected supernova, or whatever.
But don't you consider the death of the operational self a death? Or the certainty of change accumulating to make a very old individual so different from a younger self that the whole question of "self" becomes problematic? Or the strong possibility of the heat death of the universe, an imploding big bang, or the eventual decay of all subatomic particles?
I've been seeing this coming for over a decade, and I look forward to a very, very long life, but I still think that all alive to day will die eventually. It may take thousands, or millions, or billions of years. But it will happen.
Then again, maybe my understanding of life and death will be so changed after a million years of existence, that I will laugh at the foolish notions of my youth of the first thousand years!