I have the same problem with eating over the weekend. I don't go out to dinner much, but whenever I got out somewhere where there might be food, I'll eat a small salad or something high in protein beforehand so that I won't be starving and give in to the snacks. Also, I try not to drink more than one alcoholic drink, because it makes me more likely to let my guard down and eat things I normally wouldn't.
I usually have the most trouble when I'm at home during the weekend though. I have to try to be out of the house as much as possible by going shopping, or to the movies, or the park.
I've made a habit of cleaning my house if I'd otherwise just be sitting around, to get my mind off the fridge. Some other things I do if I'm stuck in the house are beauty treatments, like whitening my teeth or doing my nails. It not only keeps my focus off food, but it makes me feel good.