There was this interview with Rebecca Sugar from TheWrap. The section about Jasper was really interesting in particular:
After she’s defeated by Steven and Amethyst, Jasper refuses
the help that Steven gave to previous adversaries like Peridot and
Lapis. Why is that?
Jasper is very different than Peridot and Lapis. Unlike them, she has
a deep hate for herself because of her origins on Earth. She is
determined to never be weak or vulnerable. So at the point when she’s
the lowest, there’s no way she’d ever accept help, because she believes
she doesn’t deserve it.
Peridot and Lapis both believed they deserved better than what
happened to them, but not Jasper. She went back to Earth to face her
demons, and she lost. She’s consumed by her own self pity.
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