Very good job. The story was excellent (I sometimes find stories in games to be generic since so many approaches have been done, but your reasoning behind why he does what he does was great), but the ending was kind of disappointing; it didn't take long to figure it out with the last clue because I was already suspecting something of the sort. A number of games have done it.
Still, you set the mood very well and the music was beautiful. The puzzles didn't seem too tough to me, but like it said in game, it varies from player to player. Great job on the game!