Melania is staying in NY with Barron while he finishes his education.
I thought she looked amazing in her blue suit, didn't see too much of the ball, bits I did see were a bit cringey. I can't imagine anyone feeling comfortable, dancing in front of all those people, the world watching your every move.
I don't know much about their relationship, how they met etc but I can imagine she's relieved to be staying in NY with her son.