Welp! Though I did cackle when it was described as a 無理心中, lol. The situation mirrored the protagonist’s origin story in a sense, didn’t it? In the sense that she could’ve prevented it, perhaps? Or do you think there is nothing she could’ve done?
At least I called this one correctly 
Or did I? It seems like she had an immediate relapse… I think @NyappyTiramisu’s interpretation is right. The protagonist did have a realisation, but it wasn’t quite the one she needed to have.
It also strikes me that sexually transgressive teachers are a bit of recurring theme in Murata’s works. I wonder why…