I don't really have a quote per se, but I keep thinking of the example from Overcoming Overeating of the woman who drank mostly milkshakes for a time after she gave herself permission to eat whatever she wanted. While my diet seems more or less balanced I have been allowing myself many more "treat foods" like candy than I have in many years. Whenever I feel bad for eating these things or I feel a little bit out of control I always think of the milkshake lady and it makes me feel better; yes, I ate a chocolate bar with my lunch and a bagel for breakfast but it could be worse.
"Things are as they are. Looking out into it the universe at night, we make no comparisons between right and wrong stars, nor between well and badly arranged constellations." - Alan Watts