A Supposedly Fun Thing I'll Never Do Again: Essays and Arguments by David Foster Wallace:
I am now 33 years old, and it feels like much time has passed and is passing faster and faster every day. Day to day I have to make all sorts of choices about what is good and important and fun, and then I have to live with the forfeiture of all the other options those choices foreclose. And I’m starting to see how as time gains momentum my choices will narrow and their foreclosures multiply exponentially until I arrive at some point on some branch of all life’s sumptuous branching complexity at which I am finally locked in and stuck on one path and time speeds me through stages of stasis and atrophy and decay until I go down for the third time, all struggle for naught, drowned by time. It is dreadful. But since it’s my own choices that’ll lock me in, it seems unavoidable—if I want to be any kind of grownup, I have to make choices and regret foreclosures and try to live with them.