Stoptheworld, welcome to SR!
It is hard to break the cycle of codependency, but also very possible.
There is a lot of good information at the top of this forum in the sticky topics. Educate yourself as much as possible.
Look into Alanon or Naranon meetings in your area for face-to-face support among those who understand. Alanon tends to be more widely available.
Get your hands on a copy of the book "Codependent No More" by Melody Beattie. She has a series of books on codependency.
Another book I recommend is "Women Who Love Too Much" by Robin Norwood.
We become as addicted to the addict as the addict is to the drugs.
Recovery is possible and I have faith you will do great in your own journey of recovery from codependency!
I hope you continue to post and know that you are among friends!