It seems your definition of friendship was different - you asked her a personal question which made her uncomfortable. She felt pushed past her boundaries and comfort level. In other words, such questions can be draining and/or inappropriate (i.e. too close, too intimate, too persona). So she referred you to the group. But then you got angry. That's when her walls went up - as self-protection when you pushed her to a place she was not comfortable being with in the first place.

She was uncomfortable when you placed in a category (friend, someone you can share your moral dilemmas etc with) which was, again, too close/intimate.

When she said this question ought to be asked to the group, you could have said 'fair enough' and done just that. Instead, you were pushing her boundaries because *you* thought she was a close friend etc etc. Clearly, this is not how she felt. Her feelings ought to have been respected, rather than you getting angry and blaming or reproaching her for not reciprocating.