almost medfree: I know if I behave myself and eat well, I generally feel and do better. If there happens to be something like a family reunion with lots of goodies, or even if I decide to do some baking (zucchini or banana bread, etc.), I don't have any horrible reaction, but I do notice something tends to make my sleep worse and to feel like it's more difficult to relax in general.
I've worked hard to clean up my diet, though I don't always avoid things like soft drinks, if I happen to eat out. But it has helped to cut way back. You likely don't need to even do that, since it sounds like you're very careful about
what you eat.
I guess I don't mind one day or night of 'payback,' if I had an enjoyable time just before. For example, there is a restaurant with fantastic onion rings not far from here. But, yikes--the fat! I would only eat them once a year or so, at most now, while in the past I was somewhat more lenient. Yes, they are awesome!
I try to only eat ice cream in the summer months, and if I do, it's low-fat ice cream or frozen yogurt. Sometimes, only a bite or two will satisfy any craving I have. A little sugar goes a long way! Sometimes, a little bit of fruit will do the trick, and of course, that's so much healthier.
It does seem to help to monitor my diet, though I do enjoy an occasional treat. I just try to keep small portions when I do.