''Mama an angry thorn stabbed me.'' This quote means that a thorn made her finger hurt a lot. It was bleeding like someone stabbed her. She thought the thorn as someone was angry.
''He wouldn't be grinning like a proud rooster then.''' That means that he would be angry when they escape. He wouldn't be happy when he thought he was going to marry her. He would be proud when he was going to marry her.
''Mama, we are living like horses.'' This quote means that Esperanza and her mother are living in poor conditions. This also reminds her of horse stalls. She feels like she is living like a horse.