Your post could have been mine 6 years ago.
I nearly bankrupted myself emotionally, physically and financially trying to save my daughter. I credit this forum with saving my life and sanity. Eventually, I chose to save myself.
Surrendering to the knowledge I had no control, not even influence, over her outcome was by far the most challenging and painful thing I have encountered.
I'll never know all the details. As best as I can figure, everyone my daughter knew who was into heroin had either died or went to prison. I think it was her turning point.
Fast forward to right now, I have a wonderful 3 year old granddaughter and SIL. She/they are self sustaining. She's a wonderful mother. She jokes how I know more about addiction, especially heroin addiction, than she ever did. And she's right.
I am acutely aware that she will always be one lousy decision away from a relapse, no different than I am into my own codependency.
The serenity prayer has been and continues to be my mantra.