You can't hide from what you are forever.
Zee is back to feeling like she's just a monster. and therefor she's gone back to dressing 'Frankenstein'-like
This has been hurtling towards her like a head on train collision for a while now. Pretty much since 'the storm'. for those of you who pay attention to the storyline, you should be able to know what I mean when I say that.
This is basically the result of everything building up on her. All her stresses of staying strong in the face of unimaginable odds (stress is the main reason for the grey in her hair, now), her guilt over what all happened with Baz (everything from the grief she caused Ynen, way back to the fact it was because of her original linking with him that brought about pain for everyone she cares about, as well, and it's the reason kil'sha was able to return.. that whole can of worms), the pain of having old wounds torn open and her self-conscience running rampant on her like a tornado in her head, due to Tillivan's return and assault on her mind, having to act like everything is fine and dandy and that she has it all under control, so her family doesn't have to worry about it -or- her, knowing the impending fight with Bo'Zane is nearing, and how much is riding on her defeating him, even when she very strongly feels that fight will be her true death and she'll let everyone down and likely get them killed, the situation with Undertow, her worry for Cerzz's life and her insane inability to have killed him when she should have,, and the guilt of having kept him in Sennon's dungeons and giving him a rather easy path to harm Sanguine the way he did, Zee's own acid burns from that right, knocking her self-confidence even lower than it had already been (which wasn't that great to begin with), and the fact of having to drain Cerzz's blood and the apparent madness that ensued, that Sanguine had been witness to and broke down over..
But the topper on the ball of insanity building within Zee comes when Cerzz is suddenly 'too busy' to visit Sennon anymore. Though in truth it's because Baz threatened Cerzz to stay away like the underhanded son of a bitch he can be sometimes, but Zee sees it as Cerzz's eyes finally opening to what Zee -truly- is.
A chaotic, destructive and horrific monster. Zee assumes Cerzz finally put it all together and realized Zee isn't the strong 'hero' to be looked up to.. but a filthy creature that needs to be shunned to prevent further pain. This thought through Zee's mind tears her apart, having dealt with abandonment all her life, and it causes Zee to 'revert' to her former self.
Zee sees herself as nothing more than a monster, so she has gone back to acting as such. She's closed off from everyone who isn't 'family' (term used loosely to include non blood-related individuals she would still willingly jump to her death for). Everyone not under that definition receives nothing but hostility or indifference from her. Zee is done caring about who you are or where you come from or what your story is. She views everyone outside her 'family' to be worthless. They are either food, enemies, or just not worth her time. This attitude is mostly spurred on from her previous inability to kill Undertow, and also (though it's sad to say) from what happened with Baz. It was because she left her mind and heart open to 'outsiders' that she wavered and her family basically fell apart.
Zee has also stopped caring about her physical appearance again, beyond how 'formidable' she looks. She allows her decay to do as it pleases, she's gone back to her grungy, tattered, and punkish clothing style, the grey in her hair is shrugged off, ect.. The only thing she does try to hide are the acid burns, but that's only because seeing her reflection reminds her of her failures.
She's gone back to her general bloodlust. Ravaging cities, devouring humanoids alive, bathing in pools of blood.. (she was -going- to be covered in blood in this picture, hence the wonky pose, but then the blood was blocking out the detail changes so I skipped it)
She's gone back to being the unwanted flesh creation of Fleshwerks, to put it simply. No true logical thought, no compassion, and no holding back