I think I lost the only piece that held it all in place
A few interpretations:
He lost the girl that made his life worth living and made his life meaningful, she made his life complete.
He lost the only thing that kept him in one place (also acknowledge the other word “peace” not just “piece”). The thing that makes him feel like himself, he doesnt specify in the song what the “piece/peace” is. “She” in this song could refer to a girl, it could refer to his old music and lifestyle (things hes used to), or simply his city, “the town” hes been away from for so long. Whatever the “piece/peace” is, Abel chose to ignore it in order to do what he thought was better; but is now realizing his life is better but its not “him” who’s living it, but a version of “himself” that is at war per se with his choices.
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