In "Frothing like Foam," why is China divided in her feelings about the Colonel and the fort?

China is grateful to the Colonel for his generosity and hospitality--she thinks of being in the four-poster bed with Liz and how much it seemed to mean to Liz to be able to dress up in her fancy clothing. But she also understands the oppression and cruelty of the fort, and she is very relieved to have left it behind.