Magic Forums

Hey everyone! So, I've heard that when you dream of a loved one that you have lost, it's their spirit visiting you. I've had this before, but I've also had many nightmares of being haunted by spirits. Are these just nightmares, or does it mean something else?
I have them frequently, but they don't always take place in an area that is known to me. However, two nights ago I did have one where I was standing in my bathroom in front of my mirror, and a girl was standing behind me. For some reason I knew she was a spirit, and I knew that she had died and how. What could this mean?