I do. I also feel lucky in that while my eyesight and coordination are poor, my interests lie elsewhere so that doesn't impair me.
I have no idea what “human consciousness” is. I'm not deriding you, but I have never heard a satisfactory explanation. I kind of suspect it isn't actually real.
> What does this suggest about people that don't have kids?
There are a lot of species of wild animals that will not procreate in captivity. Take a group of these creature that is adapted to a certain environment and then place them in a completely different environment and they will for some reason lose their will to procreate even though they are physically able to do so.
I think it's the same with human beings. Technology has pushed so far and fast away from how we used to live, some of us, for whatever reason, don't procreate anymore.
If at anytime we become truly happy this hurts these goals. For example, if an old man could be building a wall or an arsenal of bows an arrows, or inventing a better way to go fishing, his tribe would be more likely to survive. But if he just sat there, content to being alive, this is bad for his offsprings' future.
You could say, well why can't he do these things and be happy at the same time? I can't really explain why not being happy leads to a better outcome for the safety and procreation of society in general, but I would assume that it must serve some purpose in that goal, or the whole concept of it would have been removed by evolution long ago.
So, I think it's better just to resign yourself to the fact, barring using mind altering drugs, that you'll never be much happier than you were on average before, or much sadder, either.
And as far as this 70 yo lady is concerned, I'd bet when this was written she was simply riding the high of accomplishing something, and probably soon crashed back down below her baseline, only to recover back to it sometime later.