Laura, first of all, take a quick look back and figure out what happened and devise a plan for future occurences. Then, once you have done that, look forward to getting through the next two or three days to get you back into ketosis. You know once you're back in the groove of things the hunger will go away and once you see the scale moving again you will get a huge amount of motivation back. You were able to get through the hunger once, you CAN do it again, and you will! Remember, have an extra shake or meal if you are having extreme hunger, or a legal snack. Just stick to the plan and you will get through. Trust me, it's happened to just about all of us. It IS scary to feel this way, I can completely empathize with you. But all is certainly not lost. And one thing that helped me through is what I said to MYSELF. Instead of focusing on how scared I was that I won't be able to get it back together, I said to myself, I CAN do this! I WILL do this. At first it sounds phony, but say it enough and it will be real and you will believe it.
Good luck! You've done so well so far and will continue!