What is your weakness?

Do you have something that just gets the best of you all the time? For me it is always sugar (but maybe I will post something on that later) but recently I have been frustrated with dinner. I am really good all day long at logging calories, eating healthy (ish) foods, trying to maintain a calorie count. But it seems like late afternoon and evening I have used up all of my food willpower and I cave to cravings and buy myself something unhealthy at work. Or I will hold out until dinner and then eat a ton of food that I don't even need. I just feel my energy/willpower is depleted. Do I need to eat more during the day? (I feel I have sort of tried this, but I still eat the same amount at night). Do I not worry as much with my breakfast and lunch and focus my food (or not eating food) willpower on dinner time? Sigh. Well, this is just another thing to figure out on my journey.