If you can do a thought exercise about a or multiple personal relationships you have with adults, and you conclude that a blatant, repeated and normalized double standard exists where if you treated these persons they way they treat you, for just one day or one week, and you know they would become enraged, furious and indignant, that their world would collapse around them without you bearing emotional / physical / mental / financial / planning responsibilities or tasks for them...
Run. Leave. Block. Cut off all contact.
Such people cannot be changed, and your life will be better without them.
No one is genuinely authentic. Maybe a few people who are incapable of doing otherwise due to issues.
Sometimes I'm not even authentic to myself. I can be different people from one day to the next. Generally it's an attempt to be better followed by reversion to mean, but sometimes not.