Wow! This was really good, I like your style - it's simple but flows nicely. I don't know this song, but it didn't really matter for me to enjoy the poem. A few bits of crit:
'You put so much trust in me.
Now I don’t know how'
I think this should be 'You put so much trust in me,
And now I don't know how'.
'I thought you perfect.
I thought you perfect.'
soo, something about these lines bothers me. I think changing them to either "I had thought you perfect' or "I thought you were perfect" would make it better. Unless I"m reading it wrong.
This is perfect!!!!! How come there are no reviews!!!!!! I didn't even read the summary, and I immediately knew that this was about Harry and Dumbledore.
You very nicely alluded to the prodigal son, which I found to be fitting, because I have noticed that JKR used a lot of religious references in her books. Like the quote found on the tombstone of Lily and James Potter is actually a scripture from Matthew in the Bible. The prodigal son image here is just absolutely fitting, because Harry may have run away, but he later comes back to Dumbledore when he "dies" and they reconcile, Dumbledore overjoyed to see his "son" coming back and succeeding.
I also have to commend the style you wrote in. I really found that using this like an actual conversation gave so much voice and tone to Harry. the way you broke your lines up helped to emphasize points that the books brought up. For example, your third line just says, "Your expectations." The "your" is really emphasized, and I can feel the bitterness coming from Harry. The way you wrote it also felt like a relationship with God. You have Harry questioning revelations and instructions, and later saying that he doesn't know anything, that Dumbledore is holding back mysteries and he is omniscient. I truly enjoyed the word, "mission" in line 13. It again not only emphasized some religious aspects, but also gave more purpose to Harry's goal than just walking around looking for stuff.
Even more eye-catching is when you wrote, "But now they say/That I can't have the truth." "They" is very ambiguous, and I actually found it to be very useful, because it puts into my mind that everyone is against Harry, which is how he must have felt many times.
I also found that the repetition of "I thought you perfect" was very poignant and made it stood out from all the other revelations. It also hints at the doubts that are inflicting Harry's mind, and emphasizes the bitterness and emptiness that Harry feels.
And then your last two lines were beautiful! Exquisite! I can actually sense Harry running away, and the fact that you didn't even say "prodigal son" really helps to make "prodigal" stronger and emphasized.
There are some things I would go through and fix. Just minor things. Your fourth line is great, but I think it would be stronger if you split it up into two lines like so:
You put so much trust
This way, it emphasizes the "me." :)
On your fifth line, it was broken up a little strangely. If you brought "how" from the line down to the sixth line, I think the flow would be a bit smoother: "Now I don't know/ How to not let you down."
Those are my only fixes!!!
So, to recap, this poem was wonderful!! What a great idea, and I'm so glad that you drew inspiration from music. This poem is definitely going into my favorites!
Keep writing! :)