There's an old AA adage about acting as if. Not sure how to do something? Act as if you do. I came across this again yesterday in a different way: acting your way into new thinking. Can't convince yourself to exercise or stop eating after dinner or be kinder to that idiot in the cubicle next to you? Stop trying to persuade yourself into new behavior, just do it.
In a sense, that's what I did with sugar. I set an arbitrary date and began to just do the behavior. I didn't eat dessert or french fries then and I don't now.
I've found myself recently knowing I need to make other changes, in fact, quite a few of them. Drink more water each day, go to bed earlier, stop turning the computer on first thing in the morning (I'm also addicted to email), stop eating after dinner, reconsider the treats I'm allowing myself even though they are low-fat and low-sugar.
I've been spending time analyzing my behavior and trying to sort out why I'm still stuck in some places and I realize how fruitless that is. That I just need to pick a behavior and act my way into the new belief about myself. Like starting right now.