If you are pulled into unconscious identification with the emotion through lack of presence, which is normal, the emotion temporarily becomes "you." Often a vicious circle builds up between your thinking and the emotion: they feed each other. The thought pattern creates a magnified reflection of itself in the form of an emotion, and the vibrational frequency of the emotion keeps feeding the original thought pattern. By dwelling mentally on the situation, event, or person that is the perceived cause of the emotion, the thought feeds energy to the emotion, which in turn energizes the thought pattern, and so on.
— Eckhart Tolle