This question is even more important than “where does my money go?” In the case of money, reality inevitably catches up. The account is low and you still need money. In the case of energy, there is not as solid an accounting as there is with money.
You need to use your energy in such a way that your personal accounts are balanced. If you are caught in obsessive thoughts about things you cannot control, you are emptying your energy accounts. If you are trying again and again to change a person or a situation, you are wasting energy. If you find yourself perpetually tired, you are probably using your energy in a non-productive way.
Wake up and look honestly at where your energy goes. Understand that you may need to change how you use energy in your life. Let your respect for yourself and what you need, what you want to create, lead the way. Put aside guilt and embrace love.