Not bad.
I liked that the beginning tied in with the end. It was definitely well thought out. My favorite part of the animation was when the child was reflecting, you blended the flashbacks well when he was with his mother in the valley. It definitely stayed linear, and was something that is relatively rare at newgrounds.
I think the biggest problem was that it was very hard not to sit here and day dream. After awhile it became tiresome just to read. I would definitely suggest using voices if you are capable. It isn't really enjoyable to be forced to read and try to watch it at the same time, and make sure that you can read it at a fast enough pace to keep up with the story and comprehend it. Secondly, you should have used a different song the second time around, especially since when you went into silence it seemed like it was going into the conclusion. At the end, it makes the viewer second guess their self because there is a fear that maybe that song would start again and it wasn't the end.
Overall it was good, but I think it just needs some polishing and then it would be excellent.