I've been throught the same thing lately in my family. I 100% agree that you have to put your foot down and do something. I am not sure that the focus on work is the answer, however, it could be in some situations.

It's been my experience that the family members I know who listen to the abusers are living in denial. The trick is to punch through that denial and instill some sense of empathy and responsiblity (the work idea covers half of this).

Unfortunately I don't have the answer. I worked hard at it for decades and I've given up at this point. I'm focusing on my own kids. I don't have the energy to try and raise adults who never wanted to listen to me anyway.