Here are links to 3 articles, from PsychCentral's archives, on the subject of habit change plus 2 articles on mindful eating. Perhaps there will be something in these articles that will be of some benefit:

7 Steps to Changing a Bad Habit

The Golden Rule of Habit Change

Using Behavioral Psychology to Break Bad Habits

10 Simple Steps for Mindful Eating | Reaching Life Goals

Self-Care Sunday: Eating Mindfully | Weightless