Described by one critic as a "cracked mirror, fragments and pieces that we have to see independently and put together for ourselves," even Sula's birthmark over one eye is perceived differently by different characters. What shape people perceive the birthmark to be says more about them than about Sula. To Shadrack, whose livelihood is catching and selling river fish, Sula's birthmark resembles a tadpole, a symbol of Shadrack's earthy nature and his psychological metamorphosis throughout the novel. To Jude, it looks like a poisonous snake, which recalls the serpent in the biblical garden of Eden and symbolizes the carnal sin that the married Jude commits when he has a sexual affair — however brief — with Sula. To others, including the narrator, the birthmark is a stemmed rose, adding excitement to an otherwise plain face. This stemmed-rose imagery is a positive symbol of Sula's persevering character. She remains true to herself, which Morrison, by linking Sula's birthmark to the image of the traditionally beautiful rose, emphasizes as the most important virtue of a spiritually beautiful person.
As girls, Sula and Nel make up their own rules and define the dimensions of their friendship; together, they are just outside what the community perceives as acceptable behavior: "In the safe harbor of each other's company they could afford to abandon the ways of other people and concentrate on their own perceptions of things." Of the novel, Morrison has said that her motivation for examining female friendship was because too little had been written about women as friends. "If you really do have a friend," she says, "a real other, another person that complements your life, you should stay with him or her. You'll never be a complete person, until you know and remember . . . what life is without that person."
However, as with any relationship, disagreements can occur that test the resiliency of friendship. For Sula and Nel, their separation offers us a chance to see the strength and beauty they find in each other's personality. Sula's sexual encounter with Nel's husband causes a void, a gap, an absence in the women's relationship and allows us to examine what happens when a close friendship is severed. At the time of her death, Sula suffers no limitations; she never betrayed who she is. Nel, however, realizes that she betrayed the "me-ness" of herself in order to have a respectable social position within the Bottom's black community. Any sparkle or vivacity of life she experienced was with and through Sula, and the novel ends with Nel weeping for all of the years she lost while thinking that she was mourning her husband~Jude's absence when, in truth, she was mourning for her lost, wonderful friend, Sula.
