Film Noir as a genre carries a deep pessimism in how it depicts the American family as well as the society at large, which makes it an excellent vehicle for critiquing the romanticised and overly-sanitized portrayals of these things. Mildred Pierce is no different in its portrayal of the family unit, as it positions the family as the source of Mildred's strife as originating within her own family. The source is primarily Veda, who not only begins an adulterous relationship with Monte, but also constantly pushes the relationship with her mother toward a breaking point with her greed and materialism. Second to her are both her first husband, Bert, with his heavily implied adultery, and also Monte, who shares Veda's materialistic tendencies, as well as Bert's apparent lust for women who are not his wife.
Furthermore, this pessimism extends into Mildred's professional life when the restaurant chain she's put so much time and effort into building is essentially ripped away, owing to Monte's greed.