I'm assuming you're referring to the sister? I guess the way you change anything. Incrementally. I would try not to over complicate it.....maybe try to detach from the emotion. Yeah, very challenging. But make changes to take care of you, your thinking, your emotions and your life. Enmeshment with family and loved ones is really common for addicts and so hard to see how to untangle the knot if you look at the whole mess. One step, one right action at a time.