Based from my imagination, understanding and the music video, so I'm sorry if this isn't accurate.

This song speaks about the guy's death. This are his parting messages to the girl, because he can see him suffering and crying over his dead body. This is proved by the song, "Say goodbye, and send me off with a kiss farewell."

"So here's your song, it's twisting me..."
This speaks of how the guy wanted to say something to the girl, but he can't because the girl won't be able to hear him. It's hurting him and he's wondering if he should just give it up and maybe he could just see the girl in the afterlife (Oh Well, Oh Well. Guess I'll see you in hell).

"And that was it, I have made it clean just across the street with my new wings.."
This part talks about how he was starting to decide to move on and leave the girl be because...

"When she smiles, it's got nothing to do with me."
She can see that the girl is moving on without him. She's starting to meet new friends and forget about him (Tell your new friends that they don't know you like I do.). But despite this, he will still keep watch over her until that day comes that they'll meet again.