A New Man

Marie loved her elderly husband and wanted him to live as long as she. People thought Marie was mad when she married an ordinary man 40 years her senior. He wasn't rich, and in fact, it was Marie who had done well in financial matters.
Marie worried that David would die and leave her alone. He was the only man she ever wanted and couldn't imagine living a day without him. As she woke each morning she looked quickly toward her husband to see if he still breathed, she spent her days worrying about the future...she was becoming a wreck.
Then one day she saw a small advertisement in the back of a magazine:
"Live Forever!"
The ad claimed that new research now made it possible to replace organs and body parts and thus you could, if you wished, live as long as you chose.
When Marie told David about the Ad he laughed, but he loved his wife and when she insisted, they made a phone call to Cryo-Age, Inc. and set up an appointment to meet with a representative.
John Page, founder and President of Cryo-Age was an affable and persuasive man. After just 30 minutes, he'd convinced the couple of his sincerity and his companies' claims. He admitted to the couple that the process was a slow one, taking over three years to complete, but when done, he assured them, David could be expected to live another 40-50 years!
Marie was anxious for the proces to begin, and using her charm and financial influence, ensured an early start date for her husband.
They began internally, replacing lungs, kidneys, heart and other vital organs. Finally, skeletal replacements and skin transfers were made, and finally, the brain was replaced. It seemed that David was, indeed a new man.
His new brain had all the memories that his old contained. He had the same traits, prejudices and idiosyncrasies as before, but David was an entirely new man. He looked, talked and behaved like the old David...but was he really David?
This, of course, created a paradox. Was David her husband, and if not when did he cease to be? It seems safe to reason, when he had his first organ removed, he was still the man she knew and loved. Same when they replaced his second. But then more replacements and improvements were made. Was he still her husband David at 30% new? At 60%? At 90% ?

Then one day, the paradox suddenly became murkier.
Unknown to the couple, David's internal organs, limbs, skin, blood, and everything that had been replaced, were cryogenically frozen and then after a five year delay, thawed and reassembled. There stood the old David; complete with memories up to the point where his brain had been replaced. Suddenly there were two David's. Which was the real one? the man slowly created by removing one part at a time, or this restructured David, once cryogenically frozen?
Legally, which was David? They looked alike and shared the same genetic code, same memories up to a point, were externally identical in every way.
From Marie's stand-point, to whom did she owe her love and allegiance? Could she make such a distinction?

And the two David's? Can we even begin to go there?
When does something cease to be itself and what defines that self?
It was, however, ironic that Marie now eagerly waited each day for what she once feared the most...her elderly husband's demise.