I realize I am not answering this question in terms of a food diary, but I hope these ramblings help you or someone!
I am far from perfect when it comes to eating, but I have developed a few strategies that help me stay motivated (or get me back on track):
1). I make a list (and add to it frequently) of why I am trying to maintain healthy eating habits (eg. I'm taking a beach vacation, would like to be able to wear some new fashion that needs a trim figure, or am trying to set a good example for me kids). You get the idea. I put the list on a note card and carry it with me all the time. When I get tempted to go astray, I whip out the card, read it, and then if I still want a ding dong or cheetos or whatever, I go ahead and have it, but a small portion. I stash multiple copies of my card in purses, glove box, desk etc.
2). I remind myself that emotion is not hunger and hunger is not emotion. So, I try not to eat out of emotion, and only eat when I am hungry. Obviously harder than it sounds. Still, when I start thinking about going off my eating plan, this idea does make me pause and rethink my motivation.
3). I have a day or two's worth of menus that are good to help rescue me from a downward spiral of eating badly. On these days, I concentrate on eating healthy food, and not so much on keeping the portions small. After a few days of eating healthy, I find it easier to regroup and then control portions too. Sample rescue menu: breakfast shake ( medium banana, 1 cup soy milk, 1/3 cup non-fat dry milk, 1 T cocoa, sweetener (I use the pink stuff), 1 scoop vanilla soy powder, water and crushed ice in a blender until smooth); Lunch is an enormous bowl of minestrones soup (from the original Moosewood cookbook) substitute quinoa for the pasta, a medium chicken breast (baked/ grilled), and a piece of fruit; snack: pineapple and cottage cheese; dinner: enormous serving of grilled vegies, 1/2 c brown rice and baked salmon. Weight watchers giant fudge bar for dessert.
4). I have found a few food substitutes when I MUST have a certain taste. For me that usually means figuring out how to satisfy a chocolate craving without wiping out 2 dozen choc chip cookies. So, Weight Watchers giant fudge bars (ice cream like) are good for that as is a cup of sugar free hot chocolate or fat free choc pudding...then after eating one of those, I get out of the kitchen (I take a bottle of water on the way out so I have no excuse to return to the vicinity when I get thirsty).
5). I have also found that I eat more when I am cold, co I drink a warm liquid (herb tea) before I decide to eat when or what I know I shouldn't.
6). Finally, don’t call yourself names. You are human (yippee). The most you can ask of yourself is to keep trying. You wouldn’t call a friend a “failure” or a “loser” when he/ she slips a little, so don’t do that to yourself either.
I hope all of that helps. I am finally at peace with the fact that keeping my body healthy is a constant project, and I'll never be done!
I also do it because I know that I want to be healthy and eating junk every day is definitely NOT healthy. 
