Are emotions non existent?

I believe emotions are non existent. I believe they are simply a state of mind, a positive or even negative high if you will. People are always talking about being in love and falling in love with someone. Not that I don't believe I have ever felt such a way, but I don't believe that the feeling I had was true. I believe that love or happiness and sadness etc are just states of mind. They are not real. For example, if someone is "In love" with someone else, how can they be married for years, and simply "fall in love" with someone else after their partner dies. Anger for example. Let's say someone killed your mother or father. Murdered them in cold blood. Of course at the time you will be full of anger and sadness, but in time you will forget. These emotions will sway. Just like being drunk or high, for a period of time your mind will experience a feeling of either euphoria or despair, but these feelings soon disappear and are gone. Like I stated before, I am not saying I have not experienced these emotions. I just believe people treat emotions as literal and almost physical entities. I personally believe emotions such as love are states of mind, they are not real and you can not truly be "in love with" or "hate" someone. Emotions fade. I am quite young to have such theories, and when I tell them to my friends and peers they think I'm crazy. Then again they also "fall in love" after being together with someone for a week. What do you think about my theory? I'm open to opinions