Welcome to SR. Many here know just how difficult your situation is. I'm glad you will be finding Al-Anon (maybe there is Nar-Anon in your area as well?).
What are the consequences if you discover she is abusing drugs in your home? Are you willing to live with an active drug addict?
She seems like someone who makes connections easily. Should you have to tell her to leave, I don't think she will be without a place to eat and sleep.
For sure more will be revealed.
Are you well-educated on addicts and outcomes and codependence? On top of the opening page to Friends and Family you will see a collection of links: "Sticky".
Click on each for useful information.
If you do not get recovery help for yourself, she will run the show in your home. So I am very glad you are reaching out!