Since the long-e is the part of the rhyme that matters (it's where the stress falls) he could have used 'my heart's bleeding, girl' and it would work just as well, but they went with what they went with and for a disposable pop song it's fine.
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The Party told you to reject the evidence of your eyes and ears. It was their final, most essential command.
If you're not careful, the newspapers will have you hating the people who are being oppressed, and loving the people who are doing the oppressing. —Malcolm X
Just a reminder: under international law, an occupying power has no right of self-defense, and those who are occupied have the right and duty to liberate themselves by any means possible.