DEAR READERS: The following Q&A first ran in 2020. DEAR AMY: A couple of years ago, an acquaintance of ours hosted a dinner party. I was only acquainted with half the people there. The hostess didn’t make introductions. One person present was someone I had met a few times. (I’ll call her “Jane.”) I knew that Jane had a partner, “Joan,” whom I had only met once years before. At the dinner, Jane was sitting next to a man. At one point I stared across the table because I was trying to determine if this was Jane’s brother, or if Joan was transitioning to male. I admit that I feel bad for staring, …