I kiiiinda agree. I don't think she's a cross-burning racist, but I think she does have a problem with black women. She was hella intimidated by Gnima and went pretty crazy being around her, and you're right that Charlie gets under her skin to an unreasonable degree -- as does Yaba, and we have no problem identifying that she has a problem with mothers, so I figure the same holds true for black women.
But all this debate over whether or not she's "really" racist or if Charlie's playing a card or whatever is really beside the point, imo. What's fascinating -- and funny -- is how she loses her goddamn mind at the accusation, how she tries to justify and rationalize and make excuses for herself, and then melts down and eats 20k calories to soothe herself afterwards. That's what we're all really tuning in for. She has the social sophistication and emotional intelligence of a toddler and the coping skills to match. She's obsessed with herself and obsessed with food, and she can never be wrong about anything, be it racism or diet tips. And she'll just wallow in this arrested development until she drops dead of the beetus or an aneurysm or both.
Let her eat cake. Just enjoy the ride.