When I was little, a lifetime was unimaginably long. But in middle age, one gets to have more of a view of how long a lifetime is.
My grandmothers just had their birthdays in the past few weeks. One turned 89 and the other turned 95. At this point in their lives, they don't have a lot of energy. They couldn't for example take up horseback riding as a new hobby at this point. When I was born, they were about the age that I am now. So, the span of life that I've seen them live is about how much time that I have to do whatever it is that I want to do with my life. And that's only if I'm lucky enough to have longevity and health.