Horrible, irrational fear of The Exorcist kind of taking over my life?

When I was around 8 years old, I was playing on Neopets in my family room after dinner. My dad was channel surfing, and settled on The Exorcist. I heard her voice, and turned around out of curiosity (thinking maybe it was Yoda... star wars phase) and the second I saw her face I turned back around, PETRIFIED. That was about a decade ago, and I still cannot take showers alone, be in the dark, I can't sleep at night-- I nap through the day... it's taking over and now I don't know what to do.