
Just checked, she was despised because of the other soul, and because of the mismatch between her body and soul, people instinctively disliked her, causing the soul that resided in Camilla’s body to die.
After that, it was corrected when Camilla’s soul returned to her body. So there was no villainess involved indeed.
My guess is that because Rania acted like a green tea bish from the start, camilla felt like she was pushed aside by her scheming, but since Rania was the real daughter who ‘suffered’ outside the family, she felt as if she wasn’t in the position to speak against her as she was the adopted daughter and Rania was actively trying to compete against her and ‘take’ her place so it’s no surprising Camilla felt that way. And you know she has always had family issues in her past life and therefore has trust issues.

Thing is, the ones who act as if she will be kicked out and as if her place will be stolen are the other nobles and even her brothers are somewhat worried bout that, the plot point itself is not really making sense, it is not just Camilla having an illogical thought, it is a mistake on the part of the author more than anything, I don't really need an explanation for the plot because I do remember it. I was mostly pointing out how the current drama doesn't really make sense in the context, as this is not a real daughter vs fake daughter plot, as Camilla was not purposefully put into the position of a lost daughter, or any kind of substitute for that matter. It seems more like the author veered off course with this, and didn't really put much thought into inserting it, just added a popular trope for no reason other than the lack of blood relation between the duke and Camilla, when the behavior of others and even Camilla don't really align with any sort of logic.
Not like she was adopted as a substitute or smth, for there to be a need to act as if her place will be taken by the presumed true daughter. It doesn't really make sense to act like that, when her brother isn't the dukes son either?