Your post touched me because my father, though retired, was also a very active man right up to the end. Towards the end much of his energy was directed towards taking care of my mother. He had a heart attack when my mother passed away and was bedridden for a while. I was amazed at how he clawed back from near death, going back to taking care of his finances and maintaining the household. Alas, he died 8 months after my mother. When I came back to the house the last time he was in hospital I noted how carefully he had organized everything which had been such a mess when I had last left (created mostly by me as I tried to go through my mother's papers to put some stuff in order). He was 76 and in his manner of leaving (I really like that word) he taught me as much about life as he had done when he was here.