I am going to ask a question that I think should have been asked as soon as we heard the boyfreind would not let her try an exorcise the entity. Did you hook up with him before or after your unwanted guest, and if it was after, how long after was it? In your first post you said this all happened about 5 years ago, that would have put you in nineth or tenth grade (give or take). Did he go to school with you, did you know him growing you, or did he just pop-up out of the blue? Also is his social life normal? I know you live together so who does he socialize with, what are his habits, also importaint, what is his back ground. We can start with this for now, and just to be clear, I do not susepect him to be the cause, but in a situation such as this, we have to know all the little details if we are to help.
