Lyric discussion by sugarkang 

here's my take:

he's 17 years old, so it's that time in your life when you think your life is all dramatic. you're the last best thing i got going could be mom, dad, lover, best friend. it's intentionally ambiguous, but it's someone he loves dearly because the rest of his life is shit. the special secret sickness could be the alcoholism like another poster mentioned, but it could easily refer to drugs. and because the special sickness has grabbed his loved one, he follows down the twisting alleyways and becomes stuck in several cul-de-sacs on the way.

the only one place this road ends is death. and since he doesn't want to die alone, he takes his life.
he is hanging from a noose at the end listening to dance music. so when he says "let me down gently," he's already dead.

the let me down gently could also plausibly refer to the drug high, but i think that hanging by a noose fits better. it's more consistent with the high drama, fatalistic mind of a troubled teenager.

@sugarkang oh god I think you're right. You make the song even darker than I thought. I thought "let me down gently" was just the police coming to gently inform him his loved one has died.

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