Why Does the Sun (or Its Disappearing Act) Transform Me Into a Cranky Cactus? Ever notice how the shift from those endless, bright summer days to the short, gray gloom of winter feels like someone unplugged your personal motivation battery? You're not imagining it! It's not just "winter blues"—it's a real, science-backed phenomenon, and I'm here to unpack why the sun is basically your mood's personal DJ.