Lindsay: how could you do this to me?!
Lorrie: what?
Lindsay: how could you go shopping with my boyfriend?
Lindsay: were you picking a lingerie for you?!
Lindsay: and he had to help you to make decision?
Lorrie: calm down
Lorrie: he asked me to help him choose a ring for you
Lindsay is angry because Lorry went shopping with her boyfriend. But Lorrie was helping him choose a ring for Lindsay.