That one secret. You know the one. The one you can't tell because everything will fall apart. It sits on your chest at night, a squatting horrible homunculus. Presses the air from your lungs. Crouches in the back of your throat and tastes like tears. You learn to lie around it, to speak lightly, to make sunshine against this darkness that is the only thing that matters because it's the only thing that scares you. Not the thing itself, not the secret; you already know what it is. You're not afraid of what you know, you're afraid that someone else will know it. It's not even that; it's worse than that. You're afraid that knowing it will change them, the way that knowing has changed you. The only good thing about this secret is that it is yours, and it has cut you from the inside like glass; why would you give this to someone else, the pain of knowing this.
And yet you want so badly to be known. You want so much for someone to want to know you. You want to be loved despite, maybe even because of this secret. And they can't know you if they don't know this, can they? You know that not telling is a form of lying. Or is not telling a means of being known and loved for who you are besides this, the lightness of you without the darkness. Or are you the darkness, and the lightness is the lie. You don't even know any more.
One day you open your mouth. You tell her, finally, the truth. You roll the stone from your throat, tell her the secret. And realize in the telling that there is so much more, the small shards that are part of the larger break. Her eyes on yours: But you've been lying to me, you've lied all this time. How can I trust anything you say now? The homunculus leans forward, touches a greasy hand to your lips, smiles at you. You knew better than to tell. Or should have known.