It really depends on the depth of the friendship.
Well, I think it's an odd question because sharing is a side effect of friendship, it's done after trusting someone enough, it does not require this to be a friendship but it's a sign of a good one.
It's not how much, but what...
What, what? Is it up the interest of one person or both...?
A friend in need is a d*m pest.
Mine is kinda dependent on my friends not choking me for the crazy stuff I do
It is about listening, being there, and being honest when asked. It is also about giving, and not being taken.