Well you got that part about him going a little insane (and around messing with drugs) after being separated from Connor part correct but he won't die. Though it will take uite some time things will gradually, slowly but surely get better. Things have to get really bad before they can get better.
I also think it might have a bad ending. With Simon getting people killed for Conor, makes me worry he's going to get caught and put in jail. Or Conor might get murdered some day. Or Simon might one day overdose OR JUST SO MANY BAD THINGS CAN HAPPEN I AM AN EMOTIONAL WRECK
Im predicting that this will be a sad ending. I feel like in the end Simon gonna fucked up real bad(like go insane or worst, dead) thanks to all those abusive assholes around him