Utter her name and two other names inevitably echo back: Arthur. . . Lancelot.
She does not exist outside of this trinity of passion and tragedy.
But within it. . . . She has been expressed in so many ways, had ascribed to her so many different personalities, motivations, virtues and faults that it is impossible to identify a single version who represents the essential Guinevere.
Guinevere is not one woman, she is many. Her name evokes passion, romance, tragedy but the image of the real woman behind it, if such a woman ever existed, has been obscured by time and myth.
Traditional versions of Guinevere are not heroic. She is often shown as helpless before the power of her own passion, driven by lust and guilt. She is often the victim of kidnapping attempts, and must rely on a champion for rescue. Her crown is not an emblem of power, it is an ornament, a symbol of her marriage to Arthur and a reminder that her adultery is also treason.
My favorite portrayals of Guinevere, and those which I consider most heroic, are those in which she is portrayed as a queen as well as a lover. She is concerned with the welfare of her people and her land, not just the satisfaction - or denial - of her passions. As a queen, she takes action, she doesn't just wait for the men around her to act. And whatever decisions she makes about Lancelot, she doesn't whimper about them.
My very favorite portrayal is in Parke Godwin's novels "Firelord" and "Beloved Exile." "Firelord" is told in Arthur's voice, and "Beloved Exile" is told by Guenevere after Arthur's death. This Guenevere is a royal woman whose family counts the goddess Epona among their ancestors, and who learned to rule while Arthur was still a tribune in the Roman army. She is proud, intelligent, fierce, passionate, and courageous. She has some terrible flaws, but eventually becomes a wiser and more compassionate human being. Unfortunately, these novels are both out of print, but for a glimpse of Godwin's Guenevere, you can click here