It may also be helpful to setup separate accounts on the PC itself for both you and the lady friend. This way you will also have separate my document folders, and you can have a better chance that any "adult" pictures, you may, or may not have, don't accidentally show up on her BB.
EDIT: My lady friend knows not to even look in my My Documents folder, plus there is a certain desk drawer she does no go in. Well she peeked in once and than told me she would never look in there again. (My special DVDs are in there)