Hello Tufchoices, Welcome to SR!
Actually, your choice seemed pretty clear to me. I think you did the right thing. My stepson is one of many addicts/alcoholics in my life. When he was on crack, he was a scary, scary young man. He threatened to kill family members, stole from people, wrecked his truck and got his next vehicle impounded. His father asked him to leave.
Since then he's been in jail, in prison, in homeless shelters and lost job after job, apartment after apartment...the whole time we would tell him we love him and encourage him to seek treatment. Only last year has he finally begun to turn his life around, but we couldn't do it for him. He had to be the one to want to turn it around for himself.
I know you are worried about your son, but you and your other children deserve safety, security, joy and peace. Active alcoholics are far more resourceful than we think. The entire family should not have to be sacrificed for the active alcoholic. I hope that this will be the end of your son's current run. He and you and your entire family will be in my prayers.