I-I-I-I did it, all right, all right, I admit it
Now pick your next move, you could leave or live wit' it
He is admitting to whatever the girl is accusing him of (probably cheating on her), and after he does this he gives her a choice “you could leave or live wit' it” because at the end of the day what he did isn’t going to go away. Most girls give a guy they love a second chance, very few leave.
Reminiscent of Pusha’s verse on Ma I Don’t love her — but more to the point.
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