I’m so sorry your friend is going through that. Unfortunately, generational trauma is real and its slows if not full on stops progress. I hold this same sort of hypothesis for the education system. Why teachers continue to repeat the mistakes of the past and continue to use teacher-centered strategies despite most teachers believing in student-centered philosophies. We model our behavior off of those before us, and that leads us to make the same mistakes as them. Slowly shedding one or two things, but holding the majority. It requires an insane amount of deprogramming and self-reflection that we are not trained to do. I hope your friend is able to get away from all that toxicity and find a happy and healthy relationship. For their own sake, but also for future generations to learn from and hopefully we can collectively as a society work to break down these toxic habits