Tell her to mind her own fucking business. You are an adult with fantasy needs. If she can understand that, then maybe you should just take off her head and move on!
p.s. It is not that hard to define a separate user account on a computer you share. Just saying...
Sorry to hear of your difficulties ikotomoti. We are unable to delete accounts once they are created.. I suggest you log in to your profile/settings and make sure you edit out any personal info - and ensure your password is complex and secure - then simply don't log on again.