Growing up in a tough area, I was sadly exposed to a lot of "tomorrow is not promised" situations. On our way to a pediatric appointment when I was around 7, we got the word that my pediatrician - who I can remember as being a friendly man - was murdered in his office a few hours before. Instead of an appointment we watched his body being carried out of his office building. Enough things happened that my main desire was to make it 21, and anything after that would be gravy.
I had good friends at my first Megacorp office, a husband and wife, that we spent a lot of time with. The husband I played a lot of various sports with, he was a very good athlete. One day on the way to lunch with a group of folks he goes back to his desk because he forgot something. He gets back on the elevator, has a heart attack, and is found lying on the floor when it reaches the ground floor. They were not able to revive him. Gone at 32.
In the past year, a friend we spoke to just before she left on a vacation with her husband, one that she was looking forward to. While on vacation, they go to sleep - and in the morning she does not wake up. 58 years old, visually in good physical shape (regularly practiced yoga). Then another friend, 75, who loved sports, we hung out a lot and went to a few baseball and football games together seemed fit, healthy and active just before we left for France in May. After we left he began feeling tired, was diagnosed the day after we returned with cancer in multiple locations, and died about 3 weeks later.
Many lessons that have taught me to enjoy each day. From a retirement perspective it has made so so grateful to have had 5 years of a quality retirement with good health, with only one potential scare so far that turned out to be nothing.