An excellent film about how the truly mentally ill maintain a calm exterior

I like this film because it demonstrates the reality that psychopathic Narcissists make their victims nervous, doubt themselves, and appear to be complete wrecks. The truly mentally ill person here is not Rachel who is traumatized but certainly not mentally ill. The mentally ill person without conscience-the sociopathic Narcissist is her husband.
I like that this film illustrates what monsters REALLY look like-not anxious, or nervous women but perfectly smooth superficially charming men and women who NEVER doubt themselves or feel fear only anger because they are entitled psychos but who maintain a public persona of calm. These are the mentally ill in America.
A question I have regarding the film: Does anyone else find Anna EXTREMELY ANNOYING? With her big nose and "prim and proper" attitude and ANNOYING pacific Northwest or Minneapolis accent, she has nerve pretending to be righteous after she sleeps with another woman's husband and her stultifying stupidity in thinking that a man who cheats on his wife will not cheat on her is SO irritating. I hate her accent, her face and personality, while I empathize with both Megan and Rachel. I am most like Megan phisically and like none of them Gratefully personality wise.