That father is the worst trash father of all trash fathers. Can he be more obvious that he freaking favors that aunt? And the mother of the FL is too naive. But glad at least FL has brains
If the female lead's mother were smarter/more cynical, she would have caught on to the scheming going on around her much sooner and none of the tragedies that befell her and her daughter would have happened -- ergo, no revenge necessary. Having two mother-daughter teams matching wits against each other might have been more interesting, but this isn't that kind of story.