Samsong and wilder did an excellent job of reviewing this already, but I'll add my support.
My initial concern was that this couldn't be that interesting. Why would it be impossible to convince your husband that you were his wife, even if you looked different? I couldn't have been more off base. My concerns were laid to rest and how.
This is such a complex investigation of identity, love, betrayal, etc. Indeed, as Sam mentioned, these are fully dramatized--not merely hinted at.
It builds and builds to the final scene--I cried and cried and then I smiled all day.