Rebecca, you might want to send Sol a note about changing names. I'm not sure about this, but I believe that a name change would automatically revert any of your TNBW content with it. It's not a fool proof solution, but it is a good start. I altered my pen name when coming to this new site and all my content altered with it, so I do think it's possible. Also, if protecting your privacy were easy--we'd all do it and not be having this discussion. It's not easy at all. But the onus to protect yourself is up to you--nobody else.
As to internet security/privacy in general--ALL comments, tweets, facebook posts, forum posts...and pretty much everything you've done, or will do on the internet--is publicly visible to anyone wanting to work hard enough to unearth it. It's a sad reality of the digital age. It IS unnerving. But it's also something you can take steps to protect yourself against. No plan is fool proof, but every little bit helps.