I realize that from the time my parent's caregiving phase ends (death), I will be the one to be cared for.
Both our couples are experiencing noticeable subjective symptoms, such as a significant loss of strength, unexplained rashes, worse insomnia (which has been present for some time), and the inability to move their bodies (fingers and arms) as much as they would like.
Of course, we all have times in our 30s, 40s, and 50s when we realize that we are losing our functionality, decade by decade, but I can tell you that this became more pronounced after the end of my parent's care.
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I believe that psychological factors may be a significant factor in this reason.
If you have cared for/observed your parents for an extended period, you have been involved in/observed the process of gradual death of a human being.
A one-choice process in which health is determined only in the direction of deterioration, not improvement, is pretty much hell.
The personality that is formed through this process is nihilism.
The only thing at the end of life is the long and painful process of death, which is not even equivalent to the effort, hardship, and glory of life" -- even if you don't study Buddhism separately, every day is an authentic experience of "all things are impermanent.
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About 50 years ago, the songs "Children Who Don't Know War" and "To a world far away" became popular.
I remember that we were made to sing at a cultural festival at some teachers' request (pressure).
I couldn't get a mm of emotion into these songs -- because I didn't know what they were saying.
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I believe that the concept of "adults who don't know/know about caregiving" will be created in the future.
It is unfortunate for those who have witnessed the sudden death of a parent due to an accident or illness.
But it is also unfortunate for those who continue to watch the process of continuous parental death that lasts more than ten years (life span - healthy life span = 7 years for men and 12 years for women).
Both are unhappy, but the "content" of their unhappiness is different, and they cannot share their feelings -- I believe that such an era has already arrived.