When Curly asked if you had stopped beating your wife he was pointing out a rhetorical trick. He was not actually accusing you of this.
Someone asked you to prove Liz C was correct in accusations. As usual, you deflected to ask them to prove she was not right. Curly pointed out the ridiculous nature of your approach with a question that is often used in these situations for when someone is asked to defend themselves against a baseless accusation.
You have obviously taken this very personally, but I think your umbrage is unnecessary.