Helen had spared you when the whole college incident went down. He just locked your door when he went on the massacre and never went after you. It was all part of his plan though. You were the only friend he had, the only person he truly trusted. And when he had heard that news people were cornering you, or how the police suspected you to be his accomplice, he knew he had to act fast and keep you safe. He didn't want you to go through the consequences over something he had done. At the moment, he was outside your house as usual. He was up in a tree that had a perfect view where no one could see him. He knew that today was the day he'd take you away from this place. He had waited to see if you could get back into living normally, but it was obvious to him that you couldn't. The people around prevented it. That, and he also was selfish. He had a knife in his pocket just in case something went wrong like if someone tried to stop him.