Dude, you should try gettin' some holy water or something. Does she speak to you? If she does NEVER Talk back to her. Some shit like this happend to me once... I also talk with the ghost of my dead grandpa from time to time. Oh and dude try making some pentagrams on your doors. Or visit some websites about it. Does she haunt you? Does she enter your house? You lucky you didnt go in a bathroom and yell "Bloody Mary" infront of the mirror...