What verses in genesis 2 are these lines alluding to? What was Bradstreet concluding about the two of them, even when they are physically separated from each other?

"Flesh of thy flesh, bone of thy bone,
I here, thou there, but both but one."

These lines allude to Genesis 2:23, which reads: "This is now bone of my bones and flesh of my flesh; she shall be called 'woman,' for she was taken out of man."

Bradstreet is concluding that even when they are physically separated from each other, they are still connected and united as one. Their physical distance does not diminish the bond and unity between them.