Lots of good advice. It is boiled down in the body builder's theme: "Strength in the gym. Health in the kitchen."
I just returned home from a weight session in the gym. We were talking about this very thing. None of us have diabetes. But, we are all in vulnerable groups. It requires a great deal of mental discipline and energy to actually make a difference. Lots of food label reading. Lots of stress shedding old habits, and in some cases friends who can't stand someone else getting and, most important, staying healthy.
After all, when all the smoke is cleared, what you are doing is a complete, forever, life style change.