I agree with 2thepoint.

She acts very childlike with you sometimes. She is the child and you are the father. She stamps her feet when she doesn't get her way and storms off in a tantrum. She doesn't seem to handle herself or some of her affairs like a grown woman. She seems to be acting out a role with you at times. She is the rebellious child trying to break free from her father, but when she needs something she comes running back for support.

I'm going to guess that if you told her that you can't be her sounding board anymore, it won't go over well at all. She will tantrum about it, and once she settles down, she will start looking at herself a little more deeply.

Because you fill a role for her, and you act the part, she feels safe. This is why she reacts badly whenever you do something such as, take a phone call rather than listen to her.