Have you read “The New Codependency : Help and Guidance for Today’s Generation” by Melody Beattie? (She is the addiction writer who coined the term “co-dependent.”)
The people who have spent time in learning to deal with addicts and addictions have had to figure out a lot about how healthy boundaries work. They have had to learn how to let go of what is other people’s business to deal with and how to focus on what is our business to deal with. You are dealing with an addict, but honestly, you don’t have to be dealing with anyone who has an addiction to profit from the ideas.
If you draw healthy boundaries, a rise in tension at first is predictable. When those close to you realize that you no longer move when they try to pull your strings, they usually respond by pulling a little harder. It is important to hold fast, so you don’t become (in their eyes) the slot machine that will pay off eventually, if enough quarters are shoved into it.
In the end, though, if you don’t give payoff in either drama or giving in, this usually dies back a bit. Even if it doesn’t, there is serenity and confidence to be had in knowing what your boundaries are, knowing what is and is not your responsibility towards those you love and knowing why those boundaries are totally appropriate and in the best interest of not just you but also those around you. Whatever way you learn to do it, doing the ongoing work of knowing where your boundaries ought to be–and where the boundaries of others ought to be that you also need to respect!–is very much worth doing. You’ll also learn to accept that people are what they are, they’ll change when and if they make the decision to do it, and your job is just to decide how and how much you want to include them in the circle of people you trust. In the end, “put not your trust in princes, in man, in whom there is no salvation.” (Ps 146:2)
Melody Beattie does not operate by any formal theology, but she’s definitely a deist. Her methods can still be accomodated by a Catholic world view.