Hmmmm okay. OOH! There's actually a couple tales I can think where the lady and the cursed one are the same and also serve as a helper character for their Prince Charming: the Frog Princess and the White Cat.

Another story that might work is Cap o' Rushes, which is a sort of Cinderella story where a noble lady has to flee her home and winds up disguising herself, ending up as a cook in another young lord's house, and then it's basically Cinderella expect the glass slipper is a ring in a bowl of gruel. (There are lots of other versions of the tale, if you wanna look on Surlalune, buuut the reasons for leaving home can be a bit squicky, depending on the telling.)