Donna Noble

Despite her humble beginnings, she was described by both Rose Tyler and the Tenth Doctor as being the most important woman in all of creation, due to the fact that she saved the whole of reality from the Daleks and Davros. To survive the side effects of her transformation into the "DoctorDonna", her memories of her time with the Doctor were forcibly erased and she was returned to Earth. She later married Shaun Temple and became Donna Temple-Noble.