We have a sense that we are somehow separate from the rest of us as if we were something ethereal that inhabits and controls our own minds and bodies.
This is what the "High Priest" of Atheism Daniel Dennett called "Zombic Hunch" and he admitted to feel it too.
I'm very surprised you admit to sense that too.
You say that this sense is just an illusion but you must agree that this very sense is a paramount in ours minds.
If you pay attention to this sense you'll notice that it's not just an instinctive mechanism. Because we can sense it when we are not in real danger and we can think about it and extrapolate it to a lot of other senses, like morality.
Did you never considered this sense can be a real thing? Why do we have this intricate sense and not just a simple instintictive fight-or-flight response in danger situations?
... the conviction that there is a real difference between a conscious person and a perfect zombie — let’s call that intuition the Zombic Hunch — leading them to the thesis of Zombism: that the fundamental flaw in any mechanistic theory of consciousness is that it cannot account for this important difference.
... and many other philosophers of mind don’t just feel the tug of the Zombic Hunch (I can feel the tug as well as anybody), they credit it. They are, however reluctantly, Zombists, who maintain that the zombie challenge is a serious criticism.
Daniel Dennett, The Zombic Hunch: Extinction of an Intuition?