Im reading the novel right now and i have to say, im quite invested in the mother. I dont think this is much of a spoiler because this is kinda signaled in this chapter, but the mother is actually barely part of the evils in the story. Shes just stupid and blindly chose Xiyan and mostly neglects Shihuan. Shes still her kin.
Unfortunately, if you think a bit father, it kinda just becomes ironic. But im enjoying her character. Author is giving a hope for a happy ending for Shihuan.