You can see at the end that it is actually the one person who is seeing herself in two roles while she is in France - one as a nymphomaniac, fun-loving, rebellious girl that she has lost and the other, stronger personality of a frustrated, rejected, bitter woman. By the end of the movie, she has rediscovered herself as a combination of these two parts and can move on from her lover/publisher, one that will never leave his family, and start fresh as a whole woman. I think the symbolism of the murdered man is killing the man that likes the stronger personality, but cannot resist the temptation of a younger girl - just like her editor lover who cannot leave his wife but will indulge in side affairs. Killing him is getting rid of him from her life and allowing her to move on - which she does at the end when she moves to a new publisher. The daughter allowing her to write the mother's book is her giving herself permission to write about her own pain and rejection. This all comes together at the end when you meet the real daughter - the symbolism still keeps me thinking of each scene and what it actually meant.