well if she didn't tell you while you were in the relationship then she is the one that missed the opprotunity to bring about change and awareness. She also can't compare you to past lovers cause its not about the past its about the moment and the future that awaits.
could be self sabotage.... scared of the commitment you to have so she needed space.
there are lots of things that my current bf is different from past lovers but I don't tell him..... He is who he is and I accept that fully.
sometimes we are all guilty of "love scripts" playing in our heads from watching fairtale movies, porn or whatever
When we play that image and compare it to the reality of our situation and their is conflict in the images well we tend to think something is wrong.
Hang in there communicate with her if that is a possiblity in repairing your relationship. Ask her about fantasies that she has running thru her head....