I think a lot of people underestimate the physical demands required to be a top model. It's not just what you're doing on set, it's the strength you have to have to survive in a cutthroat industry. It's the quick wit and the quick thinking on your feet in certain situations.
When she packed up to leave, she knew that she was saying goodbye to something important, which was not that bad, in a way, because it meant that at least you had said hello to it to begin with.