We are supposed to be a little afraid of revealing secrets. Also, I am not sure that we always need to let someone know everything about ourselves, it depends a bit, on whether it affects them or not.
I believe that the truth of ourselves is never entirely fixed. It changes and grows over time. I've known my best friend for over 20 years now and there are still new things I find out about her all the time.
That's the beauty of love - the journey into each other that never ends. You look pretty young still. My suggestion would be to walk slowly with each other and you will find the right time for telling secrets.