Oh god. How long has he been waiting to hear something like that? Months? And of course his aunt had said much the same thing, but he hadn't told her the truth. Nobody here got the whole story. Maybe because he was scared of the reaction he would get. If they would blame him as much as he blame himself, or - worse, if they'd try to absolve him of it ...

Tears start to stream down his face. He's barely aware of them, save to swipe at the ones that blur his vision. "I still should have come back. I could have saved you. I have to save you now." He reaches out again, despite Ben nudging him back. "I - I can't kill you. Please."

That last part comes out as a desperate little whisper. If that's the only to keep Ben from reverting again ... then he has to, doesn't he? There has to be another way. There has to be. He's fought all this time just to have a chance at this, and now he can't save his uncle? No.