"The mopes" refer to a state of melancholy or depression. Antonyms for this word would therefore be those that describe positive emotions or moods. These could include words such as "happiness", "contentment", "joy", "peacefulness", "glee", "exuberance", "delight", "cheer", "euphoria", "bliss", and "enthusiasm". It's important to remember that while the opposite of feeling down may be feeling happy, it's not always that simple. There are many different shades and degrees of emotions, and it's not always possible or healthy to force oneself to be constantly happy. It's important to acknowledge and process all emotions, both positive and negative, in a healthy way.