I am driving myself crazy looking for this fic. The fic deals with Quinn's gender identity issues or something along those lines. She may even be on testosterone. It's a Faberry fic and she gets Blaine to help her stretch her vocal range to sing for or with Rachel in glee. I know the song is from Phantom of the Opera. I want to say Music of the Night, but I'm not completely sure. I think there are a couple scenes with Quinn and Rachel going to a support group of some kind.
Any help would be very much appreciated.