Well, since Thorne has been with you for many years and you are still here you probably don't need to do anything right now except for work on grounding skills and calming your anxiety. Once you get with your new T you can begin to work on it. You can address your fears about it then.

I don't believe in demons personally, but if Thorne was a demon she has been a demon for many years, so nothing has really changed except for your thinking about it and being very anxious about it. So it is safe to "hang in there" until you meet with your new therapist, and just concentrate on calming your anxiety and staying grounded i nthe meantime.