So you don't live together, right? You gotta start at the beginning. No contact. And if someone was knocking on my window in the middle of the night, I'd call the police.
Are you in therapy? You need to get help to get rid of him. And I don't think I have to guess what you're worried about concerning this 13 year old boy. This person sounds very dangerous. You need to start with therapy and no contact.
Yes, I understand the constant apologizing, the being frozen out, the "crazy-making"... I was in your situation a decade ago. I was punished for being honest,indeed,as a friend put it "being human." I wasted 4 years on my ex-N, time I can't get back. By the end, I was frazzled, and I got sarcastic with "I'm sorry I'm honest and human."
I was fortunate enough to be able to move out of the state, into another time zone... my ex-N couldn't move me. I'm still far from him, in time and place. For the past decade, there's been the physical distance of being in another state--and being in another time zone.
My ex-N wanted me to "forget him" and "move on" despite all the destruction he caused. Strange to say, I'm friends with some of his colleagues... so it's awkward (especially with the one who called him "different") I was lucky I was able to move away.
So you don't live together,
"Different"--not in a good way