Now that the New Oxford American Dictionary has chosen unfriend as its word of the year, I guess it's official: all nouns are now legitimate verbs, and by extension so are their opposites. Like you, I somehow overlooked the intermediate delineation of friend as a verb, but there's no sense being pedantic about it. Language constantly evolves. You get on board or you get the hell out of the way.
New words arrive because there's a need for them. The concept of unfriending has been with us for centuries, but the explosion of social media has forced us to formalize and streamline the process. Used to be, if you became tired of a relationship, you had to be cagey about it: You'd see the person's number on the caller ID and not pick it up. You'd make up an excuse not to attend their dumb President's Day party. You'd be fortunate enough to spot them first in the frozen-food section of the supermarket, and you'd lurk in housewares until they were safely out to the parking lot. It was all about managing the gradual transition from friend to total stranger, and no ploy was too subtle.
Facebook and Twitter have rendered all that quaint and meaningless, not to say horribly inefficient. If you had to hone strategies for getting rid of every Facebook blowhard who came down the pike, you'd be tapping away at your iPhone 24 hours a day. (To those of you who already do that, I mean no disrespect.) Things are much easier now. If someone is posting too many random celebrity links, or is too frequently crowing about their Farmville accomplishments, they can be gone with a single tap. If somebody is re-Tweeting Rainn Wilson or marveling over the weather every few minutes, presto: they're banished for the foreseeable future. Unfriend and Unfollow: two essential tools for the busy online lifestyle.
It may sound cold, but it isn't. In the new calculus of social media, one physical friend who might have to use the bathroom is the equivalent of about 17 Facebook friends who won't; on Twitter, the ratio expands to one and 432. It's one thing to LOL at someone's retweet, quite another to feed them supper and laugh at their jokes and share with them your medium-quality wine. So don't be too reticent about it. In any garden, weeds will emerge. When they do, they're best pulled early.
Of course, unfriending is a two-edged sword. At some point, when you're conducting your weekly inventory of social-media buddies, you may notice that some of them have quietly decamped into the ether. Don't take it too hard; like you, they have a vast stable of contacts. Maybe you LOL'd at an update meant to be poignant. Maybe you misspelled the word lose too many times. Maybe that last "Which Horse's Part Are You?" quiz pushed them over the edge. No matter. Let them go. Facebook friends must be free, like Mediterranean fruit flies. Anyway, they're a dime a dozen.