Why Does the Other Person Suddenly Become the Victim When You Call Them Out?
People are psychologically wired to protect their self image before they protect the truth. It happens because of: 1) DARVO, deny the act, attack the accuser, reverse victim and offender 2) cognitive dissonance, they can't hold both facts, I did wrong and I'm a good person, so the facts get bent 3) self-serving bias, they genuinely believe their own edit of the story. You didn't lose the argument, you got out-maneuvered by a defense mechanism.
How the flip happens
You bring up something they actually did
They flip it, suddenly they're wounded
You start comforting the person who hurt you
Now you're apologizing for calling out the truth
The story vs the retelling
Whether they actually believe their own version or just need you to.