Lyric discussion by Comebakatz 

Cover art for Golden lyrics by My Morning Jacket

To me it is talking about life. Life is a road, there is a lot of light and hope ahead of you. You grow up and get older and the world gets smaller. You aren't alone anymore, but for some reason things just seem more bleak and depressing.
The middle of the song he realizes that everyone was right when they said life was hell, life is a prison, even though before he wouldn't admit it.
Suddenly he finds something to brighten his life again, a person. His world is lit up anew because of love.