Have you ever heard about shadow people or dark beings? Because it sounds like you have a shadow person or dark being lurking in your home from reading your description.
Here's a webpage I've found that covers shadow people and dark beings and also how to get rid of them: Shadow People & Dark Beings
“People will believe a big lie sooner than a little one, and if you repeat it frequently enough, people will sooner or later believe it.”
― Walter C. Langer