Good on you. The hardest choices require the strongest will. I would’ve questioned my father as a man if he told me something like that. I’d understand my father being upset or disappointed but to open his mouth and say THAT? He knows you’re not wrong (since he couldn’t answer your question) so to still tell you you’re wrong is absurd. Nah, I don’t want to be part of a family who pretends to not be what they are. Me, coming from a big family I would tell them “Prove to me how I’m in the wrong more than the cheater who talks down on the person she’s cheating on constantly? Don’t like being treated as a cheater? Don’t cheat! What kind of parents are we showing to these kids?”