It seems like you have to protect the finances.
Is she open to a sober living facility?
I cannot be sure, but I think you are saying she is flying back on her own, to b w the family.?
Your 16 year old is asking you to keep her out of the house.
That is very telling.
She does not want the chaos, you don't need the chaos.
How can you take care of yourself?
Alanon does not day you have to stay with an active, emotionally, fiscally, and potentially physically dangerous person.
Please take care. I wish you clarity and grace