I must admit that I'm having trouble figuring out what the question is - maybe I just spent too long on step work with my sponsor this afternoon and my brain is bamboozled.
Anyway - it sounds like there are a few worries afoot. In that case. maybe a frank and private chat with your sponsor could be useful here. Especially if someone is behaving in a way that makes you feel unsafe in the rooms - and 'stalkerish' behaviour sounds fairly anxiety making to me. That is not gossip (as long as you trust your sponsor not to repeat what you say to anyone else) it is safeguarding your sobriety.
Nobody is ever obliged to share at all. Anything.
I'd say that the Tradition 12 would be a good place to start on your research - as all AA meetings are based on the traditions, and tradition 12 concerns itself with anonymity.
http://www.aa.org/assets/en_US/en_tradition12.pdf