Symmetry

Ever plug someone's name or user-handle for one of your social-networking sites into a searchable email system (let's say, gmail) and confirm your impression that the relationship is grossly one-sided?

Perhaps it's you who never talks to them. Maybe you aren't really that invested. Maybe they're doing all the work.

Or maybe you have become someone's social-networking pal because your mutual friends all sing their praises, but it turns out that for all that you've quipped in their blog when they were quippy, or offered a shoulder to cry on when they needed one .... and when they've even thanked you for that ... they have never once commented on anything you've written in your own blog, never once initiated contact.