Despite what TV "reality" shows would have you believe, exercising like a madman while maintaining a huge caloric deficit is very counterproductive. Focus on improving the quality of what you eat and a well designed program of resistance training (builds muscle which in turn burns calories), cardiovascular exercise (improves heart, lung and other body functions as well as burning calories), and rest (this is where all the real improvement actually takes place). Rest/sleep is every bit as important as resistance and cardiovascular exercise. Overtraining is defined as placing stress on the body that exceeds its capacity to recover, it will tear you down rather than build you up.

On the nutrition side, stop thinking of food as the enemy and start thinking of it as fuel and raw material for growth. To lose excess fat (notice I said fat, not weight) you do need a caloric deficit, but a 500-750 calorie deficit 5 days a week is more reasonable. On two days a week (preferably not consecutive) plan your heaviest workouts such as your long ride or other intense training and shoot for a caloric neutral. These are growth days but don't confuse them with the "bulk and cut" of outdated bodybuilding methodology. Your goal is to fuel and intense workout without bonking, not to bulk up. Never, ever say "DIET" but rather make permanent changes to your nutritional habits that include portion control to maintain ideal body composition. By the same token, there is no such thing as a "cheat meal" or a "cheat day", anything you eat has positives and negatives and must be taken into context with the overall nutrition plan. If you have a piece of chocolate cake at your kid's birthday party, consider it to be a portion of your fat and simple carbohydrates for the day and adjust accordingly rather than flagellate yourself for "screwing up" and making drastic changes trying to undo the deed.