There is nothing wrong with you setting boundaries with an alcoholic/drug addicted parent! I've had to set and keep boundaries constantly with my mother. She's dual diagnosis. I understand the guilt that you feel. I feel it, too! In my case, my mom's behavior was so damaging, that I absolutely had to stop my exposure to it. I had to either set boundaries, or I'd lose my own mind. I've had some family members back me up, but others have said that I'm too harsh. I just have to do what I need to do, and let the other family members do what they feel they need to do.