the beautiful aspect of glimmer’s fucked up mentality with her family is she projects her own feelings of inadequacy onto them and assumes they’re waiting for her to mess up, because Glimmer views her family as unreachable standards before she sees them as people. Her entire family is the image of perfection, reflected in their character designs. Not one hair out of place.
And Glimmer is a mess in more ways than one, and she doesn’t feel like she’ll ever be even close to as good as the rest of her family. Glimmer perceives herself as a disappointment, and she projects that feeling onto every one else.
It’s why she never actually talks to Angella, because she feels like Angella thinks she’s too weak/not good enough to fight rather than Angella’s sense of responsibility when it comes to keeping Glimmer safe. Angella says herself that Glimmer didn’t know about her guilt for what happened to Micah because Glimmer doesn’t talk to her.
Micah is a unreachable idol for most of her childhood. He’s immortalized in murals and statues, and regarded as a hero and super powerful sorcerer. He’s perfect and nothing she’s told changes that, and she doesn’t think she’ll live up to him.
And Castaspella is a different story. Her Aunt is royalty and wasn’t born or married into it, she earned it and she’s well-respected. She has not a hair out of place, and she’s better than Angella at keeping her emotions in check. Glimmer seems, on some level, aware that she can hurt Castaspella’s feelings on a way she doesn’t with Angella— but it’s mostly after she’s already hurt them.
The way Glimmer talks about her achievements with Castaspella is actually, notably, to put an emphasis on Angella believing in her and She-Ra. Throwing around the two things that usually get support. But Castaspella, unlike most people, isn’t all like “yeah a bunch of kids can win a war that’s been going on 30+ years because my SIL thinks so”.
That’s not enough for her to regain the hope she lost when she was fighting the war herself. Instead, it makes Castaspella feel like she doesn’t have a right not to believe if Angella does, because Castaspella also struggles with severe feelings of inadequacy. (And, notably, deals with it pretty similarly to Glimmer!)
And part of Glimmer’s “silent” arc throughout the series is gradually coming to understand that her relatives aren’t the perfect people she painted them as in her mind. They’re people too, and they struggle just as much as she does.
After S1, she realizes Angella is not infallible and Angella starts trusting her more and Glimmer realizes her mom thinks she’s capable, she just loves her a lot. This is later kind of broken in S2-S3, since Glimmer starts leaving Angella in the dark about her decisions. (Crimson Waste.)
And as for her relationship with Castaspella, it doesn’t seem to have fully clicked for Glimmer until S5 (or maybe S4) that her Aunt is also a person and not infallible, as the way her and Castaspella interact changes. Glimmer acts more on equal-ground with her, and is ready to comfort her when she seems upset.
She even shoots SW a dirty look for insulting Castaspella, because she recognizes her Aunt might not show that it gets to her, but that doesn’t mean it doesn’t.
and the writing is kinda good there. I think they could’ve better expressed this arc of Glimmer’s, because it was… basically the brunt of her psychological issues. The idea that people are inherently better than her is something she struggles with throughout the show, and the primary reason why she’s so concerned with being replaced as a friend.
And she had to learn from SW in S4 because SW was the first (and only) person to tell her that she had an opportunity to be better than her family members, and to learn from where they failed and whatnot. Glimmer needed and wanted to hear that, and SW knew it. Even if Castaspella had offered to reach Glimmer, Glimmer wouldn’t have accepted and she wouldn’t be able to explain why.
She kind of ends up just… snapping out of this mindset in S5.
basically: Angella, Micah, Castaspella and Glimmer need to go to family therapy. (Invite Adora and DT later on, because they need the regular kind of therapy first.)