Exercise

The problem with finding the drive to diet and exercise is the main obstacle in acheiving fitness goals. You need to maintain a routine for an extended period of time pushing yourself to your limits. This requires a special mindset.
In order to achieve this mindset you need to introduce "stress" into your life. The reason you need to have stress in your life to have the drive to diet and exercise is that it induces a negative emotional state from the release of cortisol and other chemicals. And it is in a negative emotional state that you feel like exercising. And exercising becomes a relief to that negative emotional state.
You need to feel sad or depressed or angry to get the best results when exercising. Therefore you can't have positive relationships like a girlfriend that produces good emotions. When you're in a good mood you want to enjoy it and put off exercising. You also want to enjoy it by eating. When having an epiphany it induces a sensation of hunger, an epiphany is basically just a really high good emotion.
Good methods of inducing stress are to be in heavy traffic all the time. To have a stressful hecktic work environment. Loud noises or people yelling. To have negative relationships with people. To have an uncomfortable environment like high temperature and humidity or extreme cold. To constantly be in a rush or have a long to do list. To constantly have responsibilities to worry about or too much work to do.
Stress on the other hand may also induce negative side effects such as losing sleep, getting behind in important tasks, losing concentration, accidents, anger and arguments in relationships, lack of relaxation time.