> But social events are not mandatory was what I was after.
Again, it depends on what quality of life you can live with, and how you're able to achieve that quality of life. Most people would be in serious emotional pain if forced to live as hermits, which is what happens to you after you alienate enough of your friends. Depending on your circumstances, Facebook (and the leaving of it) could play a large role in that.
If somebody is really to that level of social dependency then it's a choice between being a depressed hermit and having privacy. It's still a choice. Just because one option is more obvious for some people doesn't mean the choice disappears.
