> I assume whenever you grew distant from some friends, you had other friends who you weren't distant from - it was staggered.

true-ish when I was a kid. although for most of my childhood I didn't have any friends anyway, either because I didn't "fit in" or because I'm just not a very gregarious person. since the age of eighteen, I've had the step-wise N to zero several times: once when I graduated highschool and went to college out of state, again when I transferred schools, and most recently when I graduated college and got a job. I'm not saying it doesn't suck, just that it's not particularly unusual, at least for adults. having only lived one path, I can't really say whether it's better to be exposed to this reality early, or to be mostly sheltered from it until after highschool.