Just to clarify my position.
I think it's rude to ask my host, who is already cooking thirteen separate dishes for a large amount of people, to cook different, extra food just for me because I don't like any of the things she's already making.
And the reason I think it's rude because she's already going to a great deal of time, trouble, and expense, to put together a menu which allows everyone to try a particular style of food. The entire point of the party.
So on the occasion someone made me a meal containing coriander, which I can't stand the taste of, I ate it without complaint because it was the right thing to do, the polite thing to do. The social norm for someone who is a guest at someone else's table.
And at the big family occasion when the only food available was a hog roast, and I don't eat pork because I don't like it, I quietly had a bread roll with coleslaw and left out the pork, and nobody noticed because it was polite not to make a fuss.
I also think it's rude to refer to someone as "that X person" rather than just as "X" and so I wouldn't say it myself. It's not the social norm for most people, and people objected to it. Including the person being referred to in that way, even though she has accused the OP of trying to force someone else to conform to the social norms of dinner parties when they shouldn't have to and said expecting this was nasty behaviour on the OP's part.
And that, I find odd. Because to me, one is no more different to the other. You don't ask for different food at a specialist dinner party just because you don't like what's already on offer, and you don't refer to people as "that X person" instead of by their name, because neither is polite.
And politeness seems to be defined by social norms. So you can't object to someone expecting a guest to conform to one but then also object to a poster on here not conforming to the other.
It's like expecting to have your cake and eat it. Or not having your cake and asking for trifle instead because you don't like cake and you don't see why people have a problem with that.