You can do it, it just takes practice.
I had been t1 diabetic since 1969, and managed fine from the outset as my GP was good about suggesting I ate cake or chocolate if I really felt I wanted to. But the swapping of some "bad" food for a "good" food every so often, whatever your definition of that is, doesn't help with the urges to eat a full packet of chocolate digestives in a sitting, or whatever.
I learnt to look at things differently, using some NLP techniques. NLP (Neuro Linguistic Programming) helps you train yourself to look at situations differently. Simple things are easy - for example I used to hate sitting at my desk eating my packed lunch, but then I remembered I loved picnics, so I just trained myself to see that lunch chained to my desk as a picnic.
So, when it comes to stopping after one chocolate, one chip,... I try various things e.g. "Do I really want to be a locust, not a human being?" Diabetes doesn't come into it. Sometimes I try an example I saw Paul McKenna use with a woman who was addicted to chocolate. He found the two nastiest things she could imagine eating (hers were human hair, and dog mess), and he got her to imagine they were mixed in the chocolate she had in front of her. Worked for her, and sure works for me!
I am sure your local library would have books on NLP, if you wanted to give it a go. Good luck.
