How does Knapp feel on the occasion of her sister's wedding?

At the wedding, Knapp cried. She was happy for her sister, but also miserable with Julian. By that time, they were both trapped in the miserable relationship. Knapp hated being at the wedding because it reminded her of how she was failing. Her relationship was a mess, she hated her job, and she was drinking too much. Her sister, on the other hand, had graduated from medical school and was now getting married. She also hated the dress she was wearing that day. It was a small, spandex, black dress that Julian had insisted she wear.