Are you sure she understands how to wash herself?
That may sound silly, but when I was young, about that age, it never occurred to me that I had to wash the top of my head (it made soap go in my eyes) so I didn't do it. My mother asked me and asked me about why my hair looked so nasty, my sister got in trouble for using Skin So Soft in the bathtub (my mother thought that's what made my hair greasy,) and finally my mother asked me to show her how I washed my hair ...
Kind of a strange story, but true.
And some kids are just messy. I never had a clean room (though it was never gross, just unkempt) until I left for college, and now I am a total clean freak. Make a good example and she will follow it eventually, if my story is the norm
Good luck!

EDIT: Oh, and concerning her time of the month ... I guess I'm kind of dirty about that. I always got in trouble for letting my pads bleed through and things like that, but I just never felt that sense of failure when it happened ... it just did. I found myvag a few years ago, and the author of that 'site feels the same way, so I just don't worry so much about it anymore. The only problem is laundry and sometimes staining ... but if it's taken care of right away, it's not so bad.