Here's a post about
sharing vs. privacy in friendships.
In my observation, some people have a strong need for sharing in friendships and other intimate relationships. That is how they build connections, and without it, nothing works for them.
Some people have a strong need for privacy. They share based on common interests, or if they think the other person could help solve a challenge. They connect by doing things together or discussing mutually favorite topics. They don't use sharing as a primary means of connection, and may feel that other people are prying if there is pressure to share more than they want to. (I'm in this group.)
Some people start out one way and shift over time. But I don't see it happening a lot.
Mixed relationships across this boundary are difficult to create and maintain. And if one person shifts but the other doesn't, usually the relationship breaks. Some people are worth the effort, though. Both styles are okay for people who like that sort of thing, and it's not okay to nag someone to be something they're not.
This is why most of my friends are either guys, or girls who don't do much girltalk. I cannot abide girltalk and all the shaaaaring.