I would never allow this "Friend" in my apartment unsupervised. Yes, its a trust issue, and yes, its an invasion of privacy issue, and yes, its an etiquette issue, and sadly, yes, I have criticised my nearest and dearest to DH. These are my friends/family; they are who I see and interact with on a daily basis. They are relevant to me.
But these are comments. They "stop" in a sense after my remark; however, cutting it may have been, and however much I regret it later.
The picture taking? The emailing? It makes things....more permanent, more mean, more creepy, more unforgettable, in my opinion. Maybe its a generational thing? I am finding that more and more people have no problem posting their lives on the web, and thinking this is the norm.