It's about the pressures of growing up in China where it's almost impossible for young people to get a job, and the stress level often forces people to take their lives and so on. In a way, you could interpret that "I'm leaving" holds a different meaning at the start and end of the story: "I'm going off for today" and "farewell". And, cutting her hair symbolises breaking off from this routine even though it means leaving Jian Guo whose career life has hit the slump. 'Cos in a way, that seems to be routine for many in China: abandoning others so you can advance your life, not that they've a choice to reject this way of life.