That's not how I interpreted it. I saw it as either she has had students falling for her before because she's been too friendly, or she's the student in her memory that fell for a teacher and knows how painful it is to be rejected so she doesn't want to do anything to encourage students as a teacher.
100% this. She used to be a kind, happy, and friendly teacher and had students falling for her and I might get dark but maybe this student hurt herself after she rejected her? Or went into a spiral of depression quit going to school and all of that and maybe the parents blamed her for it? Or maybe I've read too many other stories that go in that direction.
So far this series hasn't shown anything dark like that so it might just be the whole "She saw how heartbroken said student was and didn't want that to happen again"
Either way thanks for the translate and upload.