"I do believe what you are saying holds true for many and there is
evil, ghost, entities good and bad that roam the earth and do in fact take host
enter humans as well as real live parasites....."
It isn't the "evil ghost entities" it is your "friends"
that get in your space the most and the easiest. When our/their spiritual
energies extend beyond our aura, we are invading others. It's that simple.
To cast them out, learn about yourself as spirit, particularly grounding.