You are not the only one. My aunt has the same problem. His mother had to change her house telephone number because his friends were drug addicts. They had the same phone number for 30 years. Now, she doesn't have a choice. Her son was arrested twice.
The SWAT crashed her house at 5:00 a.m. and arrested her son. He was fired from his job two times. His parents still send him to a rehabilitation every week, and they pay his lawyers a lot of money. The rehabilitation isn't quite perfect, but he is getting better.
Unfortunately, he is not interested to get a job at all after he graduated HS two years ago. I am stuck with him because he is my cousin. I don't see him often because he has no responsibilities for his future. I tried to convince the mother to make him to get a job, and she loves her son. She gives him some money from her work. She works in 2nd shift. I am sure that she has no idea what her son doing in her house awhile she is at work. I gave it up, and left them alone. Maybe, the son will get older and to be aware of his situation.
Did you try to send him to a rehabilitation? Maybe, it might improve his responsibilities. It is better than nothing.