Can you explain this dream

I dreamt that I had been possessed by a ring that my ex boyfriends mother had given me.In my dream I was trying to give the demon to her but it was too late and had already taken over my body.I was trying to run up winding stairs and into the lift at the car park. I followed them down the empty streets and gave the ringback but it was too late.I then felt numb and did things I didnt want to. I eventually had an exorcism in a video shop that was large and very dark.When the thing was coming out of me windows were smashed and people were really scared but had to hold me down to make sure it was realeased. When the thing came out of me I was then back to my loving self and everyone was happy and so was I.