Lyric discussion by Silvertailstora 

Wow, what a complicated song. Well, to start...

I agree that this song is probably about trying to tell someone something important. They can't say it and they know time is passing and they'll have to say it soon, but they can't make the words come out all at once and the way they want them to ("Instead I mumble randomly"). They're so stressed over this they lose sleep and/or have vivid nightmares, but they don't want to talk about what's bothering them to anyone, instead trying and failing to hide how troubled they are with a smile.

Now here comes the hard part. The last five lines are the most confusing to me.

Either what they saw at the "gigantic spree" is what's bothering them ("it haunts me") and that's what they want to talk about in the first place, or...They were going to confide in the other person because they've realized they're going to have to pay the price for what they have to say sooner or later ("He'll have you later cause it's never free") but they see something that makes them doubt that the other person can be trusted, and they have no idea what to do.

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