To me, it is the most mysterious day of the year. The Northern Hemisphere is turning its face back towards the sun, and even though it will still take a while to notice it, the turning point is now, today. Today is when we can, from the bottom of this darkness, welcome light back into our lives.
To me, this day also symbolizes regaining hope. Just like winter will run its course, so will sadness, despair, apathy, and lethargy. Those rays of sunshine will finally appear over the horizon.