You’re not my friends.
It's harder to explain why I didn't add you than to just do it, but now there are so many of you that it stresses me out just to log in. Family I haven't spoken to in years, kids I knew in school who live across the country now, old flames that I wouldn't dream of speaking to, and it goes on, and on, until I can't remember the names of my cousins because they're all just tiny icons clogging a sidebar. I'm not going to call you to say happy birthday, but I'll hit a button to pretend I remembered because if I don't, I'm a jerk. When it's so easy to be friendly, why wouldn't I? Only now when my best friend's birthday is coming up I log in to check the date because I've forgotten, and I hit the button and that's good enough. And they will do the same for me, because we're "friends" and that's what "friends" do now. I waste hours engaging in this meaningless, worthless facsimile of friendship, for hundreds of people I barely know, and god forbid I stop logging in because then I'm impossible to get ahold of. Nevermind that you could call me or text me or meet me for lunch if you actually want to spend time with me. I'm being antisocial if I don't click the button to give you extra lives in farmville.
And my mother wonders why I don't have any "real" friends. I don't have the time anymore.