I am an alcoholic, but being so we are all co-dependent to some extent as well. I wish I had good news or news you want to hear, but I fear I don't.
In my honest opinion, you both need to seek healing, and most likely independently of each other. She must learn to become clean and sober on her own and for herself and nobody else. If she is trying to be sober to get you back or to have anything external to herself fixed, it will never work in the long term. It has to be from within and only for her.
The same goes for you. I don't know if it happened earlier in your life, but you have become afflicted with another aspect of the disease, which is pure co-dependency. Often co-dependents are sicker than the alcoholics and addicts that they love. It stems from the fact that the denial can be easier to keep and stronger. After all the alcoholic or addict has a glaring flaw that is obvious to all, as it is easy to see that constant drinking or drug abuse are not normal or healthy. The co-dependent on the other hand may seem responsible and selfless to a fault. They can justify that they are just sensitive and caring and anyone would be so if they loved an addict or alcoholic! They can find a million other co-dependents, not in recovery to co-sign their ********, and commiserate with them.
The bottom line is for whatever reasons both the alcoholic/addict and the co-dependent are very sick. They must seek healing regardless of external things, be it people, places or things and we must each one of us own our own responsibility for recovery. It may sound harsh but it's the truth. If you and your girlfriend have any future with each other you both must seek your own healing selfishly and come together later or as a secondary thing.
If either one of you gets help and recovery and the other does not, the one who got recovery would be most likely be amazed that the attraction would pass. Not to say you would not love and care about the person anymore, but healthy people are not generally attracted to romantic relationships with sick ones. I hope this is helpful.