Think of lying in bed staying awake. It's dark, you don't even want to look at your phone. You don't have the motivation. Once you fall asleep it's painful to wake up you just want to go back to dreams the happy place. Once you're in public all you focus on are the people smiling with friends or the people laughing being happy. You don't even feel sad anymore. You just feel achingly empty. If depression were a color it'd be the darkest red, because it's like a flame of happiness is getting burnt out.