Glad to hear you're reading Codependent No More, that book helped me a lot! Recognized so much of my patterns in there, and the book gave me a new way of detaching--somehow I didn't realize that it was possible to detach *with love*. I had always detached in anger, which led to guilt and reattachment! Kept me stuck.
About your friend: maybe this is your HP working in mysterious ways, reconnecting you with old friends? The fact that she distanced herself might not be anything personal towards you; it might just be that she has learned over the years that she does not like being around active addicts. I think a boundary of not wanting to be around active addicts and the difficult relationships they tend to have is one that many people end up adopting to protect their own serenity. So maybe this is a chance while your AH is away to reconnect with this woman from the new place of serenity you are building for yourself?