But I'm always gonna make you feel I don't need you as much
As I really need you so you don't use it to your advantage
But you're essential to me you're the air I breathe I believe
If you ever leave me I'd probably have no reason to be
Refers to his insecurities——he will never admit he needs her as much as he really does due to his fear that she will use that as leverage against him. However he contradicts himself (in his own mind) admitting that she is his backbone despite what he publicly says about her, and what he says directly to her.
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