As Paula suggested, eating protein and complex carbs right before you go may help. Generally, you will only stay 'full' for about an hour or so after you eat though, so you'll probably want to do it right before you go and make sure that it's dense protein and complex carbs to maximize the window of 'fullness.' 

I also think that really taking time to think about why you want to make choices that support your desire for good health, quality of life and appearance may help you see these choices as empowerment instead of deprivation. I might help to have photos of yourself at your heaviest as well as some as you want to be to refer to when you are feeling a bit 'weak.' 

Finally, it may be prudent to stock up on those dense proteins and complex carbs first, while giving yourself permission to have a some goodies, but only if you have the muscle to try a bit and not over-indulge. Finding ways to manage this is critical to our long term success, but remember that the problems you had last night are not a sentence and do not mean you are doomed, it does mean you are going to have develop some new strategies... it also means that if you stumble, like you did last night, the important thing is to do what you are doing... get up and try again. Do not surrender to the negative behavior, but BELIEVE that you have tools to make the changes to support your long term goals of better health, a better quality of life and looking the way you want to look.