Well, going back to the Kingdom Hall...it can be like visiting the grave of an old friend you were forced to destroy, as it was for me. The feeling of invisible walls pressing in on you again, hearing their zombie-like tone of voice, seeing them appear to be brother and sister...it could be intense, maybe even frightening.
Bring a Bible with you, but make sure it's a different translation. If you're just there for a talk, just sit there and read it. It'll give your brain something to do in order to filter out the Borg programming. I use it as a way of shutting it out. Writing down your precise thoughts on a notepad is also a good idea.
The most important thing to remember is that it is merely illusion. These people are under a spell, and you are not. When you leave, you may feel a bit of sadness, but you'll heal. Either way, if someone who claims to be family doesn't tell you about their wedding, that says to me not to bother with them. But then, I guess my approach to family must be different than yours. I don't deal with people who don't want to deal with me, for whatever reason. If they want these people to be their family, fine by me. Just don't expect me to be there when those people aren't.
But...remember with all that said that these are still people, whatever they believe. They don't understand. Try to stay as detached as possible. If you let yourself feel, in those moments, it could be very bad. As Chris Cornell once sang in 'You Know My Name', "Try to hide your hand, forget how to feel." I used to listen to that song before going to meetings years ago. I recommend giving it a listen before you go in there.
http://www.youtube.com/watch?v=YnzgdBAKyJo
--sd-7