Hi Katie,
Welcome!
From your experience, you know how difficult it is to overcome an addiction and you know that your husband will have to decide himself, if and when he wants to live a sober life. I think it's sad that your daughters hate him and hope that they will find peace with their father, at some point.
If you feel that going to the co-dependency group would be helpful for you, then you should go, but, if you're not sure, then you should follow your heart.
Take a look around the forums. We have two forums for Friends & Families.