Lyric discussion by lofger 

Soybobomb nailed it.

I'd almost be willing to wager my left nut that this song is indeed about "dying young", not a woman named "Diane Young".

This verse in particular makes it especially clear:

Irish and proud, baby, naturally But you got the luck of a Kennedy So grab the wheel, keep on holding it tight Til you're tottering off into that good night.

The verse is bathed in irony. "Irish and proud" shows how the person believes they're lucky. "But you'e got the luck of a Kennedy" for those of us who have paid attention in our history courses, we'll remember the strange number of Kennedy's that have died young in either freak accidents or in JFK's case, assassination.

In another verse Ezra sings: "Out of control but you’re playing a role Do you think you can go til the 18th hole Or will you flip-flop the day of the championship?"

Again, Ezra is implying that the person won't last until the end and will just burn out quickly.

"Diane Young" is definitely a homophone for "dying young" as first suggested by Soybobomd.

I agree with most of this, including the Kennedy part. But, that particular verse most likely refers to Ted Kennedy's car accident. In which he shamefully drove a pregnant woman and himself home drunk and off a bridge. She died as he escaped, swam out ad went home. He slept before he ever called the cops. All Kennedy's had really bad luck, but Ted's was of his own design.

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