She’s saying that there’s a historical racist element to the whole black man-white woman thing, and that she’s reacting to that feeling of being implicitly degraded by the cultural indoctrination that white women are supposedly preferable to black women.

It really isn’t that hard to understand.

So the cultural indoctrination that white women are supposedly preferable to black women is an excuse to feel bad about a white woman marrying a black man? If that is what you are saying then I guess it is just too difficult for me to understand.