Margaret (Maggie) Dresden, Margaret (Molly) Carpenter, Margaret Dresden (LeFay). Maiden, Mother, Crone?
IMHO, the nicknames are to distract you from the fact that the most important women in Harry's life are all named Margaret.
In fact, since Madge if a diminutive form of Margaret, I'd be completely unsurprised if Mab's proper name wasn't Margaret.