Oh. Oh. Ooooohhhhh...
The bullies went after him for associating with the girl, thinking he was her friend. And now after he got all banged up, she's going to:
1) Go absolutely feral on the bullies.
2) Do everything in her power to nurse him back to health.
3) Attempt suicide so as to make sure he doesn't get caught in the crossfire again.
Which will dissuade him from his vengeance. Because now she's treating him with empathy and kindness while he's at his weakest, when before she would bully him instead.
Surprised nobody thought of this angle earlier.