I have had something similar only the "presence" has not left. This is 12 years now. I think it is all military and has nothing to do with aliens.

Research Persinger and his God helmet. When you direct a source of energy at the right side of the head, it feels like a presence, but it is actually just man made energy weapons.

There are parts of our military and secret spy agencies and other departments that are EVIL. They are committing crimes against humanity. They are committing genocide and driving people nuts with this tech.