It is Tomie’s fault for her beauty, which is the base drive for men to harm her and go insane. This places blame on Tomie based on her appearance- in the same vein, she is dehumanized and described as demonic, her beauty being not just inhuman but sinful since she is a demon. In her most truest form, she is always revealed to the audience as a monster. She has lived experience as a woman so it would be difficult to reduce her simply to being a symbol of what men are afraid of and ultimately being a force of societal problems because she does have the right to choose and by having her say this it makes it impossible to treat her only as a representation of what men and women fear and that she is just a disease out of everything because of her rejecting a man. When she is demonized and villainized by the manga and yet also seemingly supports the ability of women to reject men she cannot just be a tool that men act through .
When she is a demon or a disease that is meant to be a symbol of domestic violence or violence against women, saying that she has the right to choose the men she involves herself with it contextualizes the statement as something bad or evil if she is a disease or demon rather than a woman asserting her autonomy as a human when she is not human. This is not to say that her humanity is what should be what preserves her from being a victim of violence, but instead with her characterization overall this line is made out to be something bad, similar to her beauty.
