actually, she was forced (sometimes directly, sometimes indirectly) to those actions by tatiana. throughout the books it’s mentioned that grace has had no romantic interest in james and that she doesn’t want this relationship with him. in the flashbacks it’s made clear that she much rather stay friends with him, it’s even mentioned that she doesn’t mind the idea of james being in love with cordelia at all and she kept trying to break him free of the bracelet, several times before he managed to free himself - here it is important to note that everytime she returned the bracelet to jamie she was forced to do so and either her own life / safety was threatened or jesse’s.
this is a very nuanced situation and though it maybe hard to comprehend, grace was forced into this situation, in a different way from jamie, yes, but forced non the less.
now as for matthew, ive always hated that scene, but i also understand that grace felt like she had no other option and this was the first thing that came to her mind to keep matthew off her back. she was raised by tatiana in a way that she only knew her feminine charms as a weapon, literally, so that’s what she used on matthew (i imagine to her it is no different than a blade, not that it excuses anything).
again i feel like every bad thing she has done can be lead back and blamed on tatiana, or belial in some instances. she grew up in an abusive household with a mentally unstable and cruel women to “raise” her, that constantly threatened her, belittled and bullied her, not to mention groomed her to be her right hand women; and later when tatiana was temporarily out of the picture (after being attacked by a demon and later while being imprisoned) belial took over and threatened jesse’s safety.
throughout the book when grace powers are elaborated and how tatiana forced her to practice them on mundane men and then use them on james it is always stated that she does not enjoy using her powers, she sees herself as jamie’s friend and has his best interest at heart - while still trying to protect herself and her brother (again she initially didn’t even tell tatiana for that her powers didn’t work on james and tries to take back the bracelet twice to free him.). this is to me especially underlined by her interaction with christoper in chain of iron, where she knows she could let him do her bidding and force him to help her but she states clearly that she doesn’t want to do that.
i do think that the matthew situation was a little different as it wasn’t directly ordered by tatiana but rather an action that grace did on her own, but to me it is a cry for help, grace doesn’t know how to help herself unless it is through her powers so even though i do not condone that one specific action i do unterstand why she did it.
and lastly, i wanted to mention again how grace is very much a victim of her circumstances and she was forced into the relationship with james just as much as he was, only she wasn’t brainwashed. also cassandra clare very much wanted grace to be a complex character rather than just a morally good character and called her actions morally grey on several occasions.
one last thing i want to clarify: i never, ever romanticized the sexual assault any of the characters went through. i believe you, anon, wrote me this ask after i compared her to suki waterhouse. this comparison: 1) started out as a joke and clearly labelled as such, and 2) is just two blonde girls in white dresses. the original post had nothing to do with grace’s characterisation, actions and least of all the brainwashing of any of the male characters
