A few more thoughts along the 'one day at a time' line.
Rather than a sweeping diet change, which tends to be so 'strange' that as soon as we approach progress we stop it, a useful tool can be:

1. Choose a change you can make right now and continue indefinitely.

(Example: could I switch to only skim milk and fat-free yogurt? Sure. Could I keep it up forever? Sure. Could I eat a (or one more) raw vegetable today? Sure. Could I eat a (or one more) raw vegetable every day long term? Sure. BUT Could I not eat roast beef au jus today? Sure. Could I never eat it again? No way.)
Then choose another one.

2. Do anything, anything at all, that makes your heart speed up noticeably for half an hour a day.

(Walk the dog. Vacuum all your carpets, hard. Rake leaves. Dance to the stereo. Swim. Anything. Before long, it takes more vigorous exercise to make the heart speed up noticeably, so you either work harder or keep it up longer. If you have a question of heart disease, check with your doctor, but most people can tolerate a speed-up to about 120 without getting winded; virtually anyone can handle breaking 100 beats a minute. If you are very weak or out of shape, you will hit that speed-up goal with very gentle effort at first.)

My worst overeat time used to be right after work; get home hungry, thirsty, and tired, and have to be in the kitchen to get dinner on the table: danger time! I would sometimes gobble so much before supper I was not really hungry for supper, then eat anyway because I was embarrassed to admit how much I had already had! Really bad plan. What helps? Eating a high-protein snack (string cheese or fat free yogurt usually) and having a big glass of water before I leave the office (about half an hour away). Then by the time I get home, my appetite is no longer raging, and I can make smarter choices. Putting the kettle on and making a pot of tea, all sorts, herbal fruit concoctions mostly, and sipping those all day/evening is a help too.

I also have tried a number of 'replacement' foods, and some are good and some are dismal. However, I am thinking that having a 'replacement' food for the foods that tempt me most is not particularly helpful, because I can also overeat on that. (This is a problem that arose for many with 'fat free' cookies and such; because they were 'good' choices people felt they could eat more. Four cookies (biscuits across the Pond) at seventy calories is not an improvement over two at 140 each, or one 280-calorie sugar/fat bomb.) For some foods one really loves, it makes sense to work them into the diet. Plan to have, say, one scoop of really good ice cream on Tuesday, with no guilt. Do NOT have ice cream in the home. Eat at home a light meal of grilled fish and a big salad, then go out for one delicious scoop. Then do not worry about craving it during the week, because you are going to go out for another scoop next Tuesday.
For other foods, go with a substitute that is not as good. No problem. Low fat cheese is not the greatest, nor egg white omelets. But if I have them with, say, salsa or spinach and herbs, they are not bad, and I am not tempted to eat too much of them, nor do I miss the egg dishes because I have an 'okay' (not great) egg dish once or twice a week. I am using an imitation cream cheese which sounds gruesome but is okay; not great, but okay, but this works out instead of butter on my multigrain toast because if I were using really good rich cream cheese, or butter, I would be more tempted to put too much on. I think choosing which things are worth the 'splurge' and planning around them, and which things one can 'fake' and not miss so much, could help. My current favorite for chocolate craving is a big glass of skim milk with a good slug of chocolate syrup (which a lot of people do not realize is fat-free, and a much better choice than those powder mixes that are way too much sugar and not as much chocolate taste); not a bad health choice, fat free and lots of calcium, very filling, and definitely a good slug of chocolateness. If my friend really n-e-e-d-s a chocolate candy fix, she uses Tootsie Roll Midgets; they have to be unwrapped one by one (lots of visual reminders of how much you have had!) and must be chewed quite a while, so there is lots of time of having that chocolate flavor in the mouth.

I know I have spent a long time realizing that enough, is, in fact, enough.
A patient told me something great one time. She said, "One bonbon is good. Two bonbons are not twice as good." It is so easy to think, this is so good I want more, and not notice, the later bites are not nearly as satisfying!

Peg Bracken, who wrote "The I Hate To Cook Book," says the neatest diet she ever heard was given to a friend of hers by a doctor. It was, 'No meat, no wheat.' That's it.
I also saw what looked like sound advice on a book cover. It said, "Eat food. Not too much. Mostly plants."

Celtaddict, 13 down and lots to go.