Have you tried the aquarium salt? ( at the very least it might make her a bit more comfortable). Just don't treat for too long and only add more salt with a larger water change. My betta has come back from near death with just some salt, and no lights on for a few days. Really, he was collapsed in a ball on the bottom of the tank and could barely swim to get to the air and he had turned all black. It was terrifying, but he is now prancing around and giving everybody attitude! Don't give up! Good luck.
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