Yeah i'm not feeling it, she was shown to be completely evil and sadistic consistently. She cut up Daleth before any of this happened as far as I know.
Don't see any reason to forgive or help her just because she was rejected.
I never expected this randomly visiting ghost couple to blow the lid on most of the biggest mysteries of this manga, which the mangaka kept delaying for so long.
Sade absolutely doesn't deserve redemption. Sorry, but everyone has some kind of trauma in their life, but that doesn't justify making everyone else' life traumatic too. Sade was just being petty