Christmas, as this song reminds, is about taking sin, rejection, tragedy, fighting, and pain, and turning it into something positive. How?
In this little song, it is the trappings of the Christmas Holiday that overcome the grief. Carolers, snow, lights, chandeliers of hope, the street, and the sea all invade the pain. It all really makes no sense. That is why the Muse can use it, and the Muse doesn't have to work hard to expand this to ANY environment invading our little corner of depression with a slowly dawning joy. The world is a whole bunch of pain. And then, out of seemingly nowhere, we experience the universe in our own way and our outlook improves a little. That is the Muse in our lives. We are capable of only failure without this guidance.
Both pain and triumph are there to show us God's love for us personally. The Muse can even use artificial creations like our modern Christmas remembrance to bring us up the the top edge of the pit of dispare in which we might be and show us another place view life from.
Keep listening.
Enjoy.