hi, sorry about your pain too. i also feel like you are heading in the right direction. you have nothing to feel guilty about, he's where he is in life because of the choices he's made for himself.
you are not stupid, its hard to watch a loved one self- destruct. we want to help, to be there for them but unfortunately there is nothing we can do except save ourselves.
it took me 21yrs to get to where you are now so i think you are doing great. keep the focus on you. you are in my prayers.