This isn't only in Japan, it is a phenomenon that is spreading across the globe. Japan is first hit because of the strong disparities between generations. Truth is, the internet brought about a lot of things so one could have a constant "window out" from a single room. Most of us know precisely what I am talking about. I would like to theorize that this is only one of the things that facilitate such isolation by maki…
I'm with you on this, my dad has actually remained "messed up" financially- and career-wise, even though he was a brilliant student and young civil construction engineer back in the day. Of course I love him and think of him as one of the smartest and most intelligent people I have ever talked to, but I cringe at the thought of what would have happened to him on an emotional level if he were to had access to Facebook, for the reasons you describe above (he and mom live in the countryside now, I've brought them an old PC some time ago but thought it best not to install them Internet).
For a possible solution, I think that at some point we will be forced to retreat from this online social mess we've become entangled in, if not by our own will maybe at least our subconscious will force us to. Could be that it's all just a craze.