ever since you take the choice of poisoning the two annoying dudes at the school all the events are Cassidy and the perv of him pushing her to humiliation, every room you go into the school will have that, still no choice of finally killing him, is this a bug?
roll back and just open an old save file if it keeps crashing then that means a recent option you took made the game corrupt and can be fixed by going back before the option that corrupted it or by saving a file before the event, thought by now I doubt you'll need this advice