> Before Facebook, if I lost someone's contact information, and drifted outside of their social circle for a long enough time, chances were I would never ever see or speak to that person again.

I was nodding along at this until I read your second paragraph, then had to go back. Apparently you think this was a bad thing?

Losing touch with people is natural. Having to explicitly sever a relationship is awkward. But without a natural pruning function, it's easy to end up with a thousand shallow relationships and not enough deep ones.