Lilian's parents were actually scholars. Since Mother is a woman, she was discriminated in the world of academics. However, Mother and Father both worked together in research while Mother is conceiving Lilian. Father promised to put Mother's name as co-author in the paper to fight with the gender discrimination but when the paper was published, she found her name was nowhere to be found. When she confronted with Father, he just told her that there was nothing he can do as the academics world can be unforgiven if someone tried to cross over the public belief. (In this case, it was the public belief of women were inferior to men. If he put Mother's name on the paper, people would doubt the credibility of the research, no one would take the paper seriously so it will end up just collecting dust on their shelves nor would Father earned the achievement he did because of the paper.)
Stressed with her husband's betrayal, she became mentally ill. She needed treatment but because she was a woman, they refused to treat her. Without proper treatment, she suffered more and more so when she broke her limit, she killed the husband. Thus why the rumor about House of Dead was spread. Even in death, no one pitied her of being discriminated against just because she was a woman. If only she was given proper treatment, she would not kill someone. If only, the husband put her name as the co-author as he promised, she would not get sick. But what was done is done. She became the villainess in their story.