Bijou
I was 64 when my husband died and two years later came back to the bungalow which had been let for twelve years and I had to completely redecorate and restore the furniture which had been ill used and restore the garden. Never had time to be tired! Then I spent my savings until I was 82 on holidays abroad and at the same time had to give up decorating and gardening.
My niece graduated from university when she was 60 and at sixty five is still teaching. Has two of three grown up sons still at home who don’t help much.
My mother went out to work for the first time at 67 when my father retired because she couldn’t stand being with him all day.
At the age of 99 I still manage with only one hours help a day. I do have arthritis in both knees and have survived cancer twice. The only medication I take is painkillers but I do take vitamins and have a healthy diet.
It is not a question age but a state of mind.
Bijou I'm truly glad that you, and apparently your wider family have excellent genes and admirable life habits. But it's not helpful to state that that's because of a state of mind.
For many, many people it's much more complex than that - e.g., a genuine health condition which causes tiredness amongst other symptoms, or a mental health problem which has been triggered by stress but is nonetheless genuine.
Telling these people that it's just a state of mind is only going to make them feel even worse if they believe you, because then they'll have to carry the burden of guilt that they've not been strong enough to cope - which isn't at all the case.
It's a bit akin to when the old fashioned doctors used to brush off things like endometriosis pain and things like depression as "just women's problems" or "pull yourself together, man!" My own father used to tell me to "pull your socks up" "grow a backbone" etc., until after my first hospitalisation at age 12, when he was given an excellent book about depression (I wish I could remember the title) and realised that it is in fact in some people - I'm one - an imbalance of chemicals in the brain. (It also runs in families.)