There's a story in al-anon (I think in one of the readings? Not sure), the refrigerator story.
If you were on the phone with someone, and they told you your refrigerator is blue, but it's white, would you stand there and argue with them "My refrigerator is not blue? It's white!" They're on the phone - they can't see your fridge, they don't know what they're talking about. But me, I would totally stand there and argue with this person that my refrigerator is white, not blue!
So there's the saying "My refrigerator is not blue, my refrigerator is not blue..." You know he's wrong, and we're told "don't argue with a drunk alcoholic" for a reason. It saps you of anything constructive and you're left continuing the argument mentally while he's going on with his day. No thanks.