It's hard enough trying to untangle the interesections of gender identity, sexuality, economic necessity, and sexism without tossing a completely unreliable narrator into the mix. The narrators of gender-crossing stories already have enough motivations to be unreliable, even setting aside the question of the language and concepts they have to work with. They may be motivated by identifying the narrative that will make their audience most sympathetic (which may change with the audience). They may be motivated by trying to protect a spouse, by presenting her as naive and ignorant.