Lyric discussion by sokorny 

Sounds like a partner has "run away" from a relationship possibly unhappy with the situation, not wanting to commit or wanting to find greener pastures. The narrator however is hoping that like gravity they will come back to them (realise falling in love with them is inevitable).

The first verse seems to suggest their love is inevitable and the brightest, so why fight it?

Moves along to the partner leaving (run away), and the narrator can't understand why ("you said you would stay"). They hope they will return ("see there's still life in a dying tree") to them.

There is no closure at the end of the song, as far as I can tell ... still waiting for them??

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