Stop overthinking it, I told my reflection in the bathroom mirror. The lights reflected off the yellow walls, casting a strange light on my face. Stop overthinking it. They want to be here. You're having a good day. Breathe.

I didn't know why I had to convince myself. It had been a wonderful day. At lunch, my friends brought me presents and a cake they had made. The whole grade sang “Happy Birthday.” School got out early, and we poured into the halls whooping and shouting. My friends and I had sat in the sunshine and looked over my presents. I had necklaces, a mix tape, a crumpled photograph of two boys I didn't know, and a rock with a gummy bear stuck to it. The boys wove me a crown of branches, and the girls and I lay in the sun, our limbs tangling until you couldn't tell whose hand was holding whose or which heartbeat belonged to whose body. It was the first time in a very long time I wasn't worrying over every word and gesture. The hunch in my shoulders had quietly slipped away. This was my day.

Reassuring myself of this, I stepped out of the restroom and back into the crowded restaurant. Turning the corner, I saw my table was empty. Panic peaked as I turned toward the exit just in time to see the door shutting behind my friends.

They had forgotten me.

I collected my things and walked slowly to the door. I should have rushed to catch up with them, laughed at their little mistake, and forgotten it. But I was suddenly so tired that I could feel every bone in my body growing heavy. The words rushed to the front of my mind: You should've known this would happen.

I took another step, and a memory rushed in: the birthday before this, when I had left the room to get my phone and returned to find that everyone had left for ice cream. The birthday before that, when I had stopped to tie my shoe outside the Thai restaurant and my friends surged on without me.

The next stride across the floor brought back another memory: chasing my friends down a country road and coming around the bend to discover they were gone. I stood, bare feet aching, tasting the dust on my tongue that they had left in their wake. As long as I concentrated on the dust, I wouldn't cry. They would come back, and it would be fine.

By this time I'd reached the restaurant door, and my pulse quickened, but my steps grew even smaller. My mind went farther back – running after my friends up basement steps, all of us laughing. Then they turned out the light and locked the door behind them. When my friend's grandmother finally realized where I was and let me out of the cellar, I didn't feel like laughing anymore. “Come on, Vivian. It was just a joke. We would've let you out eventually.”

Every time I was left behind, I would catch up, they would apologize distractedly, and I would try harder to make myself worthy of their attention. But this time – this time was different. Why should I keep trying? In seventh grade my mother grounded me for three weeks, and I begged, “Please, Mama. I won't see my friends again. Mama, you don't understand; they'll forget about me. If I don't call them, they'll forget who I am.” It was constant work getting them to remember me, but in my mind, that was what friendship was: working harder than they did.

Leaving the restaurant, it finally started to sink in. People were always going to forget about me. When I was two my daycare providers accidentally left me in an elevator. I would always have to remind others I was there, because why would they remember me? I wasn't worth remembering. I was forgettable, always slipping between the cracks, easily shouldered out of conversations. I was done trying to make myself into a solid figure, something tangible that left evidence of my presence.

Down a block I could see my friends at the stoplight; I shuffled slowly toward them. There was no way I could go home – my parents didn't expect me until late – so I decided it was best to join my friends as though nothing had happened. They wouldn't find it to be of consequence anyway. I was familiar with the quick apology before their magpie eyes slid to something more interesting. I realized then that there would always be something more interesting.

The boy with dark hair spun around to speak to someone and caught my eye. “Hurry up, Vivian. Why are you so far behind?”