I am watching “peers” and family retire at 62, 64, 67, or 72 an then die a year later

That happens, usually when people retire because they can't go on anymore. The other group that it happens to are the ones whose job is their whole identity. When they quit, they lose the will to live.

Then there are people like me. I retired at 55, did a lot of travel and volunteer projects, then went back to work four years later because I found an interesting job with good working conditions. Now I'm 70 and will probably work another year. I didn't quit the first time because I was unable to continue, I had other reasons, and I'm fully able to keep on keepin' on now too. I don't have any expensive vices and don't buy into consumerism, so I'll be able to retire late next year with a higher disposible income than I have now from working. I still have things I'd like to do that'll be easier if I'm not holding down a job (e.g., going on month-long bike rides). Nobody knows how much time they have left, but I'm fit and healthy and enjoy life, so chances are reasonable that I'll get quite a few more years with decent quality of life. And if not, no use fretting over what you can't control.