[mikeash]

In your scenario, I would absolutely assume that they hated my race, and that they had merely hidden it. Overt racism is not tolerated in a lot of places, so racists usually learn to hide it. Sometimes it comes out under stress.

Non-racists don't suddenly start making racial comments they don't believe just because they're in a nasty fight.

Racial discrimination doesn't have to be absolute. Saying it can't be discrimination because she didn't reject this guest up-front is nonsensical. When someone shows you who they are, believe them.