This sounds exhausting.. Sometimes you have to just tell people like this respectfully that they need to stop and just accept the aftermath but if you cant do that, do your best to fade out. They seem the type to talk shit regardless.

I hate these situations since like you, I am usually a very patient person but depending on how much unjustified bullshit people give me I have no problem telling people like it is. It can be kathartic to clear the air and anyone she talks to who actually knows you will most likely understand shes full of it so I dont think that would be an issue.

I absolutely do not recommend living together. Not worth spoiling your university experience.