I am so very, very sorry. There is nothing more painful than watching someone you care about get lost to addiction. I am glad you were able to have a relationship, that she was still a gentle soul. Without doubt, she went knowing she was loved. That matters.
I know what you mean. I too just want to scream "run" to some of our newcomers. Sometimes I do just that. If a person can go through life unscathed from addiction, or the affects from it, they are winning.
Huge hugs to you.