If I ate as you described Id be very unhappy, often hungry and have very little energy to continue the diet. The difficulty comes from the combined influence of types of food, how they influence metabolism/blood sugar, your mental state and stressors. A holistic approach is typically better than a simplistic or dismissive one, though "keeping it simple" is best. E.g. finding time in daily routine for food prep (buying coffee, bananas and bread to unpleasantly spike your blood sugar in your case), identifying and restricting binge foods, identifying ideal portion sizes, making reasonable comprimises with family/house mates, replacing comfort eating etc. You cant white-knuckle a diet and expect it to work till you die, for many it will (and should!) be a lifelong process.
