Hmmm, I'm afraid I don't remember anyone as groundbreaking as her, but there were two females in The Gods Themselves. Dua, the alien from the second part, was the only one trying to prevent the destruction of 'our' universe. She had an interesting story, and she was striving to define herself; but the whole concept of their three-gender society (basically, three sexes: clever 'men' who do science, not-clever 'men' who raise offsprings, and not-clever vain idle 'women') will make you weep. And then there is Selena, in the third part, who helps the hero to save the world and convinces him he is not too old for them to love each other. Not much in terms of independency and empowerment, but not that bad.