He does change.
What happenes from this point on:
1) Connor has to tell the court what he and his friends did to Evy, in the events up until they crashed into her car.
2) Connor keeps trying to talk to Evy, but she keeps running away during school.
3) Third day of school Tory (Evy other bully and Connor's now x-girlfriend but Evy doesnt know that) and her lackies pins her in the locker room of her school, and harasses her as always. Evy doesn't even her her words instead once she comes close enough, she punches her in the face. Tory thrown back threathens to tell a teacher, when Evy reminds her what it will sound like to her she just got her ass handed to her by Evelyn Meyers the nerd of the school.
4) Connor finally corners Evy to talk to her. Evy has now come to believe the entire adventure had to have been a dream. That Matty was never real and her brain just kind of inserted Dream Matty with Connors face because he was the last person she saw before the crash.
So as Connor corners her he puts his hand in her locker. She sees an opportunity. She backs away and slams the locker shut on his hand with all her might. He's a baseball pitcher... and his hand just snaps. As he's crying in pain and gets his hand out of the locker he goes to grab her so she turns around with her heavy AP Bio text book and smacks him in the face with it like its a baseball bat. His nose breaks. The WHOLE SCHOOL sees! Well not the whole school but most.
Although as she walks away he says something "I thought it was you for me and me for you!" A saying that only one person knows Matty!
Now Evy doesnt know what to believe. It end with Connor leaving a note on her bedroom window. She looks out and he's paying the guitar outside of her house. Singing her favorite song. Then long winded speech about how much he's changed and how he'd lose everything for her. Then he finishes with "I only want to be your Matty again"
Kiss scene and the end.
