I am going to comment, only from a very judgmental and self protective way, being I got anxious reading this, anywho,
Walk away. It's easier to get 30 years sober, ( seemingly impossible for me) or, get recognized for performing in a band called, psychedelic horseshit, at the Grammys, rather than pull a relationship off like this.Elements of chemicals, and your obviously very loving intentions for her, will leave both of you mentally spent and drain you of life and happiness.
My best friend, and former"special lady friend", complained to herself out loud, "why do I wind up with old men, who are over medicated, drug addicted, morons?" I dont talk much, and said nothing," I understand. But something is wrong with her "picker" and mine as well. It seems with my limited view, that something might be wrong with your choice of personalities...
I know this as absolute fact, that taking care of you, and your needs.are your best known, and most qualified self care advocate.This is a cheesey reference, though sounds really true is,
"The way you choose to self talk in a deprecating manner can affect your mental as well as physical health,...correcting this is you first and most effective form of self defence".- Bruce Lee.
Protect yourself and dare to be selfish.Walk away. And allow room for growth. And a future with someone who feels for you, as you feel for her. She might need a catalyst for her to choose as well. My God, I sound like my therapist.

Practice peace and take care of YOU
Phobophobic.