I think the mother got dealt critical damage when yandere told her she will be fine on her own if she Rei. Well, maybe not. She seems to have been neglected since childhood so I doubt the mother really cares that much. Don't neglect your children. It fucks up their mental health really badly. Just don't. Also if you don't build a close relationship throughout early childhood you will never get the chance again. They will see you as unreliable and they will choose to rely on other things instead. Arguably it can be justified with having to work to feed them then I guess a close relationship and their mental health can be sacrificed. This can lead to them having addictions though so you have to be careful.