Lyric discussion by joan_of_snark 

I think this song is about postponing-- almost procrastinating on -- dying. It's called "Til The End of Time" because neither person wants to die. It's a cheery song because there is a sense of control over one's own death.

"You can't live your life on your deathbed... let's not let it end this way"-- 'this way' being death.

"Like sweethearts carved on a headstone Oh why even bother, it'll be here tomorrow It's not worth it sleeping alone" -- don't bother dying, the grave will be here tomorrow, and it's better to sleep together than to sleep alone in your tomb.

"And look at you and me still here together... And we've come such a long long way Let's put it off for one more day"-- Why bother leaving the world we know now? We can die later.

I think the "words" mentioned in the first stanza are fears about dying, which the singer tries to mollify in the rest of the song.

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