Middle Age
I think it's finally starting to hit me. Though I'm not much over 40, middle age is starting to close in. While I was most worried about physical degeneration, that hasn't turned out to be much of a problem. There's a hidden blessing to being not athletically gifted, and it is that it is harder to see one's skills erode when they were meager to begin with.
Psychologically, however, it has been more difficult. Most of my close friends live in other states. It is hitting me that there are things about my personality which I may not be able to fix. And while I've never had particularly grandiose visions of achievement, I didn't expect that the rest of my working life may be characterized by having to work very hard just to hang on by my fingernails.
The good news is that I haven't fully accepted this, and that these are the problems of prosperity.