But as I said before, Misery's curse would compel her to save the island at the expense of her own life, because if Ballos was killed or freed there would be no more crown bearers. For what other reason did she take Sue hostage to protect the core? What Pixel said makes absolute sense. Balrog can't save Misery from herself.
It's a very good point, though I would like to offer the theory that after possibly destroying the Crown and its bearer; that its influence might wane for a period of time. Just a theory.
Why would she protect the Undead Core, if not because of compulsion? Maybe to protect the island? As she said, if the core is destroyed, the island will fall; bringing about its supposed destruction... (though it didn't look like it was so bad...)
After the the curse is broken in the best ending, Misery seems to be sticking around, or watching Balrog fly off, or just being nostalgic or something... Don't really know, but I'd like to believe/theorize that she has a connection to the island, with or without the curse. And that she would protect it for her own reasons.
Balrog seemed happy to leave, but Misery didn't seem to be going anywhere...
Just offering up alternative possibilities...
"Balrog can't save Misery from herself." What's that from? Are you referring to something Pixel said in an interview? Or how Misery brought the curse on herself?