Collapsing

As far as I could see, Sally Samules was not okay. And it killed me inside. Once upon a time, Sally Samules had been my very best friend. We had been best friends since diaper days - our moms had met in one of those prego yoga classes to help the mother with her breathing as she squeezed a baby out of her vag, and when Sally and I finally arrived - within a month of each other - our parents had put us together and we've been inseperable ever since. Everything in my life was Sally and I, or We. I wasn't a single individual, and that was just fine with me. Sally was my other half, and without her I wouldn't know myself anymore. But lately . . . it seemed as though I didn't know Sally.
I don't even know what happened. One day, she's fine. Completely, 100% herself. Hyper, upbeat Sally. We were at a Patent Pending show and we got pulled onstage and sang into the open mic, and she looked so happy. The happiest I've ever seen her, actually. The train home wasn't any different either. We chatted excitedly the whole way home, smiles on our faces, going through the pictures on my camera to soak up as much of the night as possible. But first period the next day ... there was just ... something different. She just wasn't herself.
At first I just figured it was because she was tired from the concert, and then as the days progressed into a week I blamed it on her period, which always comes around the time I get mine, too. But week progressed into months. And as the months went on, Sally grew more and more distant from me, tearing a small but noticeable hole in me.
Within the course of 4 months, I watched her slowly disappear. She would often come into school, eyes bloodshot from lack of sleep, dark circles haunting her face. She was falling apart, and I refused to let her go down without me.
On Christmas, my family went over to her house as usual. It was a tradition that we had Christmas dinner with them. When Mrs. Samules answered the door, her face was grim and she told me Sally was upstairs in her room.
I knocked three times before entering, and when I swung the door wide open I dropped the Christmas gift I was holding on the floor. Sally had dyed her beautiful white-blonde hair red.
"What did you DO?" I asked, walking over to run my fingers through her ruined hair.
"I hennaed it. I needed a change." I stared at her with her bloodshot eyes and pale face.
"Who are you?" I asked quietly. She burst into tears, curling into a ball, shutting me out.
She cried like that for a while, huge sobs that rocked her whole body. I just sat on the edge of the bed and watched her cry, letting her get it all out. When the sobs turned to sniffles, she grabbed a tissue and blew her nose before looking up at me.
"Sometimes, people just fall apart. There's no explanation. We just do."