well, I'm thankful you made the right decision and got out of this relationship - as it would have taken you down the "heartbreak road" for sure!
Try to remember that you did NOT cause her addiction, you could NOT stop it no matter how much you love her.
Morn for a bit - that is OK. Know that many of us reading this (me included) are jumping for joy knowing you just dodged years of heartbreak and disappointment.
Good for you! I'm proud for you.