Melodramatic behaviour is behaviour in which someone treats a situation as much more serious than it really is. `Don't you think you're being rather melodramatic?' Jane asked + melodramatically melo·dra·mati·cal·ly `For God's sake,' Michael said melodramatically, `Whatever you do, don't look down.'. if you behave in a melodramatic way, you become more angry or upset than is really necessary