Because they are habits!
I'm eating much better right now than I have in years... limiting my diet and carb intake and exercising due to Diabetes...
I'm having a really difficult time this time... I used to be able to shed weight by just eating lightly. Now... I have to limit thing and exercise. The only issue... since I'm formerly very healthy my body remembers and I'm gaining more muscle mass than losing fat. I'm doing Cardio Based Workouts and the machines are pushing my "level" up and up.
Yes, I know. I'm just going to have to push through it. It sure does SUCK!