so disappointed

what is wrong with me? no matter how much i tell myself im going to back on track i just cant seem to do it. i eat one thing i shouldnt and that spirals me into an evening of filling my face. i know i CAN do this....i mean look how far i've come already (211 to 176 <now>)! so why can i not do it now? every time i blow my day i regret it the next. maybe if i make a committment to come and report what i eat here everyday i can feel like i have to be accountable to someone (even if it is just myself) and will help me stay focused. i just dont know anymore.