Hm. I am similar to your girlfriend. Mostly because I like my privacy and enjoy doing my own thing. It makes me feel like I have my own life. I do give the basics though as that is just respectful. I also stick to what I agree to and in that way have integrity with my loves. The more I do what I say and say what I do the more they trust me and the more freedom I have to do my own thing.
I ask a million questions of my partners simply because I am interested. I never thought there might be an imbalance! Does your girlfriend know you feel like this? Maybe she is just not aware its an issue for you.
I would suggest discussing what information you want to know from her and what info she wants to know from you. The necessary stuff. Then the rest can be talked about if either of you feel like sharing it. If one of you asks the other what happened then that should be okay I think. If neither of you want to reply then its shouldn't be held above the other. Sometimes I just don't feel like it because its not interesting and I would rather talk about something else. I have partners that trust me though and don't have similar considerations to you. Perhaps in the moment you could say that it would make you feel more secure if she were to answer but that you will deal with it if it is really a big deal. That is if you actually would be able to deal with it. All that would be up to you.
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