My boundaries are not about those who use drugs... they are about me. How do I want to live? What makes me happy? What makes me sad? What can *I* change that will give me the kind of life that brings me joy?
You sound very much like you are getting in touch with .... you.
Be strong. As you probably long ago discovered, nothing you do, or don't do will change her addiction. That will be up to her... in her time (and that of her Higher Power).
I wish you well. And send prayers for clarity and wisdom (and a nice soft bed).
((hugs))