To be totally and completely honest, I think that most people don't actually care. They don't want you to talk about yourself and if they do, it's like "oh my god. shut up."

To be honest as well, if it was me and I was like "How're you?" and that's one of my opening questions, I wouldn't really expect them to start pouring their heart out to me. It's a simple "break the ice" kind of question whilst you sit down and all that, I think. Although, with one of my friends, we ask eachother the same "How're you?" about five times in a conversation because then one of us will start talking and 'pouring our hearts out'. I think it works a bit better that way but I know exactly what you mean by not knowing when it's classed as acceptable.

It's been so long since I've had the kind of "get off my chest" conversation with somebody that isn't my blog.