I read the fic in like 2008 on Fanfiction.net, and it may not even be around anymore. I remember Harry suffered quite a bit of abuse at the dursleys and was very depressed and no one really knew. Back at Hogwarts, all the students have a lesson where they learn a spell to play a song that is like their internal song or whatever and most are normal and kinda quiet, but Hermione does the spell on Harry and it plays Breathe No More by Evanescence and plays throughout the whole castle because his pain and mental health are so bad. I think Snape ends up taking over watching over him and Draco and essentially reverts Harry back into a child, and they get transported into a Snowglobe until Harry works through his trauma and ages back up. (However, that MAY snowglobe bit may be another fic entirely, I've read A LOT of drarry fic)
We believe you are looking for Growing Pains by SensiblyTainted (190k, M)
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