A parents obligation to their children is more nuanced than your implying, setting an example isn't the only factor. Not to mention abuse is used to break your will to stand up for yourself, and even if that weren't a factor, communication isn't possible with people unwilling to listen.

Relationships are a two way street, but when you've got kids., it's not just about the relationship with your partner anymore

[–] LustyArgonianMana@lemmy.world -5 points 2 weeks ago

He stated that he wanted control of finances as his main motivator, not abuse.

Yes, the best way to teach your kids how to handle abuse is by being a role model. Sometimes that means leaving the abusive parent and making a safe place away from the abusive parent. How can an 18 year old learn the skill of leaving their abusive parent if it was never modeled to them and the nonabusive parent stuck by them no matter what?