We have our bottom, too, and I guess my thought after reading this is that you are the only one who can decide when you are truly done. Questioning and over-analyzing is so easy for us, we have been doing it non-stop with our addicted loved ones. We are also accustomed to being treated badly. We retreat, recover our strength, and then head right back into battle with something we have no way of mastering, beating, changing. We have to change ourselves. We have to decide we are worth more than all that. If the relationship is meant to heal, and thrive, it will do so because of the hard work of both partners. Work to accept the truth of your own VALUE to yourself.
And if you haven't, read CoDependent No More by Melodie Beattie. Very instructive for the likes of us. I send you peace and acceptance and serenity.