Eden's character doesn't go to great lengths to hide who she is. Her only crime is not correcting the assumptions her new society friends have of her.
She drives her beat-up car to these society affairs without being intimidated by the valet(s) who have to park it! One might assume that if she was hell-bent on deceiving people, she would have borrowed or rented a nice car to go to these fancy affairs. Even when she is found out, she refuses to shirk her responsibilities with the charity auction.
Anybody can identify with a character that is put upon by family members who rely on her, yet continue to make little digs or comments suggesting that she's a failure in some respect. Hellooooo? I'd love to see the symbolic hands raised in the audience during those scenes in the movie! Kathy's well-to-do sister, who happens to be married, doesn't lift a finger to help 'baby-sit' their father, who, by the way, doesn't seem all that incapable of taking care of himself. To me, he's just downright lazy - a typical male from that generation. Doesn't want to get a cup of coffee for himself if he can get some female to serve him. (My dad was the same way.) Then there's the toady co-worker at the supermarket who thinks that Kathy shouldn't ask for anything better out of life. She should just settle and accept her lot - and, hint-hint, go out with him on a date, even though she sees him strictly as a friend. 'People like us should stick with our kind', he says, or words to that effect.
Great writing, great progression, great unfolding of the characters, who finally put all their cards on the table at the very end! Hope I haven't told too much. But even if you think I did, I want you to watch this flick anyway if your local station is showing it!