Some authors have conceptualized depression as a "depletion syndrome" because of the prominence of fatigability; they postulate that the patient exhausts his available energy during the period prior to the onset of the depression and that the depressed state represents a kind of hibernation, during which the patient gradually builds up a new story of energy.
What I know for sure is that pleasure is energy reciprocated. What you put out comes back. Your base level of pleasure is determined by how you view your whole life.
I believe everything is energy. I believe that the meal you serve yourself, you prepare, is energy. And if you serve it to your family, it's your gift of energy to them.
The energy of hatred won't get you anywhere; but the energy of forgiveness, which reveals itself through love, will transform your life in a positive way.