Why is loung unhappy

Without knowing the specific section your question pertains to, my answer will be general. Loung is unhappy because her family has lost their home. They are forced to move from place to place for safety reasons and are often hungry. Over the course of the novel, Loung's father is executed, and the family is separated before Loung's mother and geat meet the same fate as her father. Young, Chou, and Kim are then fostered out to separate families. Thankfully, the children are later reunited.