You are not your thoughts. You are that which witnesses your thoughts. For instance, if you are thinking about money, you are not the money. If you are thinking about God, you are not God. If you are thinking about your enemy, you are not your enemy. You are that which can witness these thoughts.
When you witness selfish, rude, mean, angry, bigoted, impatient, hateful or any other type of sad thought, you must simply ignore it or change it to a loving, peaceful, gracious, divine one to be happy.
This is true free will. When we are not in touch with our inner Witness and are identified with our thoughts, we often suffer. When we witness our thoughts, we can control our reaction and choose actions that bring joy, peace, and love. Exercise this free will always and you will live happily ever after.