The darkness is not something that can be fought. It’s not even something that’s there, it doesn’t exist. Everyone tells you that it’s only inside your head - look, it’s perfectly bright outside! Get your shiz together!
The darkness isn’t real. It is not tangible, you cannot touch it. There is no blade that can release it from your veins, nor does it suffer pain or fear, and tears cannot come from it as it has no substance. You cannot see it, taste it, smell it - all you can do is feel it, but without the added benefit of seeing it how could it ever exist? Nothing you do not see can truly be real - isn’t that what atheists argue?
You look around at all these other people and yes, you happen to wonder if you’re strange. If you’re crazy. Because it’s crazy to be affected by the darkness like that, when the darkness doesn’t seem to bother anyone else. The darkness doesn’t control their feelings so much, or their thoughts; but it must be there, right, because the darkness hovers everywhere, over everyone. After all, everyone has the same thoughts, just to different extents.
And if you are crazy, wouldn’t it just be better if you left? Because, everyone knows crazy people eventually lose it, and you don’t want to hurt someone. But no - that’s just the darkness again, and you know it, but it feels so valid it hurts.
That’s the benefit of the darkness. It can’t hurt itself. It can only hurt you.
There’s a thick dark snake coiling at the base of your stomach, wrapping around your esophagus until it chokes you with bile and your heart hurts from lack of air and finally your eyes fill with tears and they spill over, and there’s an overwhelming sense of relief. Because crying means you’re human. You are not some creature or a person who is haunted by a vengeful ghost lusting for blood - you’re human, and these are emotions. It’s been so long since you cried you didn’t remember what it felt like and know you know it’s pure relief, nothing more or less than the insane outlet of emotion that you’ve desperately craved so long. No letting of blood or sin could create this absolute apathy, this dead exhaustion that allows the darkness to leave for grey sleep, if only for a couple hours.
There’s a monster that lives in your belly, growling and hungering and those sounds drive you on, they drive you forward although you know the darkness is directing you down the wrong path but that path you’re being driven down is barred on either side by brambles so you don’t even know where the right path would be anymore. You know that monster wants food, it always does, but you can’t allow it to have food. The darkness is telling you - “That monster will die soon. Just leave it alone. You don’t need to feed it. You’ll feel better, I swear.”
You know that’s not true, you know the darkness is lying to you but the monster scratching at your insides - that pain makes you feel real. You’re human. You exist. You feel things. If you don’t feed that monster you’ll continue to hurt, you’ll continue to exist, but who knows what will happen if you do? The monster will be content and the pains will stop, and the darkness may withdraw for awhile but you know it will come back, because it always comes back and whispers sweet nothings in your ear that you know are all lies hissed out through a smile but they sound so real and so sweet, and the darkness is so convincing that you forget why you ever wanted to live with the light in the first place. The light is too bright, too blinding, and there are so many bad things that happen that living in ignorance with the darkness seems like a better option.
So you don’t feed the monster in your belly.
There are leeches on your fingers. You don’t know how long they’ve been there - you’ve personally always been disgusted by leeches but one day they were just there, the bloodsucking savages always asking you for more. They wanted to drain you dry, and your poor heart could barely take that, racing with fear that its beloved blood might one day be all gone from its children the veins.
But the darkness tells you that’s a good thing.
The heart is too weak, it says, so obviously it would fear those leeches. But look at them, they’re nothing more than blobs with teeth - they don’t even hurt now that you’ve gotten used to them, do they? And really, would it be so bad if they did steal all the precious blood? Blood isn’t all that attractive anyway - everyone likes those lifeless vampires now. Who would even care if you were gone? After all, you’re a MONSTER all on your own.
And then it would laugh at you and whisper sweet nothings that sound so true, and the leeches would suck and suck until the tears streaming from your eyes seemed more like the last of your blood and your wrists were pale and aching, and you would go to sleep with blood on your fingertips and palms and tears on your cheeks and dream of falling, falling so far that the darkness can’t reach you anymore.
Falling up.
In your head, you know none of that is rational. You know lying alone with the darkness whispering to you is unnatural, and you know the fact that the warmth from your blankets never truly seems to reach you in any significant way is scary.
But then, that’s what makes you a MONSTER. That’s what makes you crazy. That’s why the insane brings so much relief. Because you must not be normal.
In books and movies, those who aren’t normal always turn out to either be the bad guys or the heros. In no way are you a hero - heros don’t associate with monsters. Heroes don’t exist in the darkness.
You must be a villain then. You must be the one destined to lose - and if you’re always destined to lose, why don’t you just die?
If you’re the VILLAIN, if you’re a MONSTER  -  no one would care.

de·pres·sion: noun
1. feelings of severe despondency and dejection.
2. "self-doubt creeps in and that swiftly turns to depression"