This situation sounds a lot like my daughter at 18. I too went through the
"my house/my rules" and tried to control every aspect of her life, both in and out of my home.
Trying to control her lead to mutual resentments and eventually she walked out the door and into hell.That was more than 6 years ago.
I think she was in the express lane to hell, no matter what. The more I tried to prevent and protect her from reaching her destination, the deeper she went. My role in all that happened, especially protecting her from the consequences, enabled her. Manipulating her into three back to back rehabs was a serious waste of time, energy and money.
She needed to experience hell and all its consequences to find the strength to pull herself out of it. She eventually did so when she she decided she had had enough. That every one of her drugs buddies was either in prison or dead probably made a serious contribution to her decision to change her own life.