@cekkk The question you pose is great food for contemplation or discussion. Let me tell you a story.
My Dad died too young at 74, leaving my Mom on her own - sort of - with 6 kids, grands, many friends and activities she kept on going. But she told me many times her heart wasn't REALLY in it any more.

Yet as age and illnesses crept up on her, she...kept on going.
I was one of her caretakers and confidants as she aged and we had a number of wonderful conversations. After my Dad, her dance partner of 56 years dies, she never wanted to dance again - she told me "I closed that chapter." She still came with us and listened to music when we danced, never missed a live performance she could get to - but didn't dance.
For the next 15 years, she and her sister often traveled to new places together and had new adventures, just the 2 of them with, or with me or my cousin. After a trip that was more difficult because of their health (they were both over 80) when I offered the next adventure she repeated "I closed that chapter."
Some years later, she and her sister simultaneously decided to sell their winter homes in South Texas. By that time, my husband and I were retired and traveling. We offered to take her back there, rent a place by her friends and visit - she thanked me and said "I closed that chapter."
And so it went - she still took joy in that which she was able to do, and in visiting with her friends, kids and grands, but she closed more chapters - managing her own home, making big family dinners, baking, driving her friends places...
Finally, after a particularly difficult illness & hospitalization she went to stay in a palliative care place, trying to get back on her feet to go to her apartment. One day, when we were alone, she asked "Will I ever get back there?" I told her only if we restarted her PT (which I had done with her many times) and she said "bring me my walker tomorrow and let's do it." The next morning, the director met me at the door and told me "she changed her mind, you can put it back in the car." That was Monday morning. On Friday, after seeing and talking to all of her kids and grands, and a few of her friends, she closed her eyes and closed the final chapter.

As I age, I have had to let go of a few things so far, and I try to think of those as closed chapters. I hope I am as graceful as my Mom as life continues.
Sue
PS I just had a wonderful visit with my auntie, who at 96 has closed a few chapters but is still active in her apartment community. The women in my family (both sides) tend to live 90 or more years so I expect to have a lot more chapters to write before I am done.