Not even me. Today has been a struggle for me. I've been dealing with some emotional baggage - almost always emotional eating or boredom is what derails my dieting.
It's so easy to think, "Well, I had that piece of cake today, I guess I'll eat everything in sight and go on a huge binge!"
Self-forgiveness works better. OK, so you went off the diet at 8:15. Go right back on it at 8:25! It's ok. Forgive yourself and move on. There's nothing magical, it was just one little cheat, don't do it again, and keep moving forward. Don't get discouraged. It's just one occurrence. It's only going to hurt your diet if you don't get right back on the diet and keep going.
Onwards! And let the scale move downwards!