Whoa, y'all are reaching here. OP said she didn't want them to feel the need to come out UNLESS they were trans "So I can support them"

OP fucked up, it was a really bad moment on both parts and she fucked up in telling someone else. I don't think, she ever meant to hurt her son but it does sound like she tried to be open but trying to give big news to someone during a stressful time like right before family comes over, doesn't seem like... good timing for a big talk. OP fucked up in not just going with: "I love you forever, I'm happy you feel safe to come to me with this" and saying "I don't care" but I don't think OP is fully the asshole here. It just sounds like a comedy of error and YOUR re-wording it to sound worse.