Congratulations on Nebula, and congratulations on tricking me into reading Fantasy. 
 This story in its essentials, felt like a modern day retelling of two 
 Brothers Grimm 
 fairy tales - Bearskin and Old Rinkrank that I barely remember from my childhood (my memory might as well be wrong here). What I loved about the narrative was the ambiguity that followed Tabitha and Amira, like they were already part of a well expanded universe, the details of which readers are free to imagine. In this retelling or extended act of passing reference, Author intertwined the essentials of both fairy tales into one lovely story, making them female centric and in poles with the original perspective. My ambitious and embarrassing attempts to understand the metaphors are given below. 
 Number 7, from a Biblical view point represent perfection or completion and number 1 stands for unity or oneness, the numbers which the female protagonists of this story identify themselves to be bound in by magic. (view spoiler)[So Tabitha before reaching completion of penance(of her and her were-wolf-would-be-man husband) by exhausting the 'seven' pairs of shoes, gets to taste the 'Apple' of Glass Mountain(which could be argued as this story's Eden). She then decides to be 'one' with Amira and leaves her baggage, thanks to the new found wisdom. And they both leave the safety of Glass and Iron(their personal paradises), for 'Away'(Earth) with nothing but the company of each other and the sense of freedom. (hide spoiler)] 
 I think I might have heavily misread the 'things', this allegorical reading was supposed to explore the nuances of. Nevertheless the lovely prose will have every reader covered for sure.