By reminding yourself that you bought something with that $200, a hard life lesson. It may not be what you wanted to spend it on, but you did get something for it. It sucks, there is no changing it, but at least you walk out of this situation a bit wiser, and won't be doing that again. Only thing to do now is forgive yourself for the mistake, hold the lesson learned, and move forward. Beating yourself up is only added misery. Are you going to do it again? No. Anything you can do to change it? No. So move on, lesson learned, forgive yourself.