Me (19m), and my sister (20f), went on a camping trip recently. I was really excited but it went downhill fast.

For context, my sister, let’s call her V, recently broke up with her now ex-boyfriend. She was extremely depressed, so I suggested going on a camping trip, she always loved those when we were younger. She agreed, but now I wonder if she just went because I wanted to? I feel extremely awful.

V was seemingly normal when we arrived, maybe a little less talkative, but I understood why. She barely said a word until a few hours later. She said she was tired and wanted to sleep. I laughed at her, and responded. “Really? I’m usually the one who sleeps first, it’s literally 4 pm.” I immediately regretted saying that.

Her whole facial expression changed, and a sense of unnerving dread was burning me alive. Her calm, slight smile changed to a dead, lifeless stare. “Well, you can sleep if you want. I’ll just be bored. Alone.” I sighed, this was unlike her. The sense of dread had gone away, as her little smile came back. She thanked me and immediately laid down.

I left the cabin to take a walk around. I barely had any service, but I still managed to text my friend, W(m21), and tell him about how weird V was acting. His response, which I had expected, was that she was probably tired from being stressed out. I felt the same sense of dread fill my lungs as I struggled to breathe. I heard a noise, like a croaking frog, and turned around. V was on all fours, and staring at me. “What the fuck?” I fell down in shock. When I showed any reaction towards her, V immediately ran away, like a diseased animal. I can only describe as she was limping away.

When I finally regained myself, I ran back to the cabin, only to be met with V sleeping, as if she had never even left the cabin in the first place. “V! What the FUCK was that?” When she awoke, she asked me what I was talking about. “Let me look at your hands.” She refused. “Let me look!” She slapped me, I could feel the dirt and grass on my face.

She started pleading with me and saying it was a mistake. But, anger overwhelmed me. Before I even knew what I was doing, I had locked her inside the cabin and I was driving down the road. It’s been about two weeks since then, and the guilt has overwhelmed me. Reddit, AMITA? Should I go back and set her free?