I know you said your mom has had individual therapy and couples' therapy, but family therapy is geared differently and may benefit you. A good family therapist might be the way go in helping facilitate better communication, be a type of advocate for the children, etc. Your mom isn't stepping up the plate and being the adult here and sounds like she hasn't for a long time. Kids can feel rather powerless in those cases where the adult is not really being an adult. They need an advocate. Many people need various types of therapy. When one doesn't seem to work, try another. She may also benefit from someone who specializes in addiction.