I think, the basic gist of the PV is that "do it again" occurs very often.
The yoyo spinning, the repeated dance move, the balls juggling, even the camera angles moving are in a circular motion, it's like everything that just keeps repeating and repeating...
I also would like to add that towards the end when she walked to a new area and there were people from the "destruction" area to the "safe" area (u can see ambulances and soldiers), it's like... her moving to somewhere safe and different, and how there seem to be people (I have yet to confirm if these people are the dancers and yoyo boy doing the things before, but if so, it wouldn't explain how the juggler was in the safe area if the purpose of the safe area was to condone the people doing circular/repeated motions).
Anyhow, the "light" at the end, seems to be "the light at the end of the tunnel" to me. How she went from walking in a debris, to a "safe" area, to finally the light. It's not a dream I think, but more like a walk through destruction and how continuing to move on seem to bring you a new beginning/the light.
But um well, I wasn't very pleased with the PV cos, most of the symbolism in the PV are just a nod to the title, and there doesn't appear to be anything too deep/amazing yet. This tried to be a walking proud/1 LOVE kinda PV but failed imo.. and like what Raleigh said, don't understand why they made such an elaborate set only to barely use it.
The beginning with her in the house was fantastic though; I just wished they didn't make the PV a walking PV with her 2 big dogs... : /