Through the Ghost Lyrics Meaning

I actually have an interpretation of this song, so, what the heck. I believe this song is about someone the artist once knew that committed suicide, for example, a lover. Consider the lyrics, "a city of dust" could well mean the nothingness considering dust could easily be considered ashes. Not only that, but when he states "did you finally find a place above the shadows so the world will never know, the world will never know you like a do" somewhat reflecting upon the fact that they've found a place "above the shadows" which could be interpreted as 'shadows' for corruption. So perhaps they found a place in 'heaven', or wherever they should be, away from the darkness and corruption of society they had been avoiding. And, continuing on, the lines "And now that you've lost tomorrow, is yesterday still a friend?" somewhat states of death if you think about it. When someone loses tomorrow, they are no longer there to 'have' it. So, my conclusion is that this song is about someone the artist knew that has committed suicide, someone close to the artist. I could probably drag all the lyrics into this interpretation, but that would be rather long and drawn out so have a good day.