I have a friend the same way. The friendship is going on about 5 years now. I have accepted she's a bit pushy for details, so immediately before she can ask anything, I volunteer some information I feel free to give then redirect conversation on her by asking about something in her life.

What I have funny about that, is that she is really wanting to talk about her life. I guess all this time she was drilling me for info on my life, she really wanted to talk about hers.

It seemed to help me with this approach. Now, I enjoy talking to her.