No you don't.
Just click the tabs at the bottom of the page. You should be able to switch pages that way.
EDIT: My mistake, I just checked and you're right.
EDIT 2: Okay, I'm not crazy - I checked with the devs and you used to be able to click tabs for empty pages, but it changed at some point before the game shipped.
Here is the solution we came up with - it's not very sexy, but it should at least help you keep track of which saves are yours and which are hers. You can go into the game folder and change the name of the saved files to something that makes them easier to identify (like your name). The save will then display with that name instead of with the timestamp. A little cumbersome, but it should at least solve your immediate problem.
Thanks for bringing this up! It's always good to hear what kind of functionality people are looking for with this sort of thing.