Content notice: morbid thoughts, indirect references to suicidal ideation.

The noise has returned.
It’s a scratching sound, like someone is dragging their fingernails across the inside of my skull. It’s as if my head is a coffin, and someone has been buried alive inside it, and they’re trying to claw their way out.
The noise sounds frantic. It feels more desperate this time. I’m trying to fight off the despair, to keep calm and save what oxygen we might have left, but it’s not working. The panic is creeping into my thoughts, and showing in my eyes, and seeping down into my fingertips. My hands are shaking and my breath keeps catching in my throat.
The one place it doesn’t show is on my face. The corners of my mouth stop working properly, the muscles in my cheeks fail to contract, my brow does not scrunch or wrinkle or rise. My face is blank and empty. It has become the perfect mask to hide this relentless noise behind. I know I’m supposed to recognize this a sign that some connection between my muscles and my feelings and my mind has ceased to function properly, but it’s hard to care when it’s such a relief. People don’t usually see your trembling fingers or how you keep swallowing or the way your feet drag; most of them only look at your face, and if your face is empty enough, you’re as good as invisible.
I prefer being invisible right now. When people try to talk to me I just end up feeling guilty because I can’t hear them over that damning sound. I’ll try to force a smile and nod and make affirming noises at the right times, but the smile never looks quite right and my voice is a little too loud. Everything about me seems strained, and I can tell, but I can’t seem to find a place between trying too hard and not trying it all; I can only slide from one pole to the over, and I either seem dishonest or inconsiderate. At least when I’m invisible I know others won’t be wounded by my bewildering existence, with all its rough surfaces and torn edges.
Every once in a while, when I manage to drag my feet past my doorstep, I see other invisible people with masks over their faces and shadows in their eyes. We never speak more than a word or two, if we speak at all, lest we alert others to our presences. Speaking isn’t really necessary when two invisible people meet, though; you already know by virtue of being seen by them that they must be invisible too, and that knowing doesn’t need to be put into words. It’s a relief just being near someone who can see you, someone who does not need you to explain. It’s a comfort to be able to just be for a moment, to just exist without defending yourself or hiding, without having to be completely alone.
“You can see me?”
I don’t answer. I try, but all that happens is a strange twitch in one corner of my mouth.
“Do you hear it too?”
I try to nod, but I’m moving a little too fast and my motion looks more like rocking than nodding. It’s okay though; I can tell you understand. You light your cigarette while I take the last drag of mine. The scratching gets louder, and louder still. I tell myself I’m too old for this, but the noise doesn’t care. It’s determined to find a way out. I have to walk away before it starts climbing down into my throat and tumbling out my mouth in sobs and jumbled strings of words. We share one more quiet moment, nodding silently to ourselves. We exchange a brief but understanding look before I step away. I try to wave but I only manage to move my hand up to the wrist; my arm stays hanging. You still see it though, because you know, and you nod again. I fade away down the street and you fade back into the concrete, and we both fade back out of sight.
We exist unseen except to each other, but we exist. Or at least, we existed for a moment.
We passed each other, and the moment passed us.
We pass by. We pass on.
We all do.