People usually say that darkness is merely absence of light.

No, it isn’t, at least the spiritual darkness isn’t. It’s an active satanic compound, like a squid’s ink, that sticks to you and inhibits your sight. It covers your spiritual eyes and tries to reach into your soul and corrupt you in ways that will make you destroy everything good in your life, curse God and die, and then have nobody else to blame, because the choice would be your free will. The darkness would just persistently nudge you in that direction; but you would have to choose to believe that it’s right.

This is not an opinion, or a matter of belief, or philosophy, or guesswork. I’m currently looking at the mechanism that does it.