She didn't process it right then, but later she realized they wanted to leave her to die.
It made her dizzy.
"Don't let her drag you down!"
"If she doesn't want to go..."
She needed... to sit. To breathe.
She did not want to die!
All she had to do was wait for her dad. He would never leave her to die. He would come, and take her back to the cabin, where it was safe. She could share her best books with Clem. Rebecca could have her baby in a clean, warm place.
She only had to breathe, and wait.
When the pain spreads in her cheek and the voice demands that she move; she jumps up. She obeys. She doesn't dare do otherwise, even though she's dazed. Confused. Terrified. Why is she being hurt now? What did she do wrong now?
And while the stinging fades, the confusion does anything but. Because it's not Carver, not Troy, (not her dad - but it never was her dad, was it? It was really all Carver, that's what Clem said, right?), but Clementine. Her friend.
Why did her friend hit her?
"Why didn't you leave me?"
Because she has to know - did Clem want to leave her, too?
"Because we're friends."