In 1894 in Munich Richardson married the Scot John George Robertson, whom she had met in Leipzig where he was studying German literature and who later briefly taught at the University of Strasburg, where his wife became ladies' tennis champion. In 1903, the couple moved to London, where Robertson had been appointed to the first chair of German at University College, London. Richardson returned to Australia in 1912, in order to research family history for "The Fortunes of Richard Mahony", but after her return to England, she remained there for the rest of her life. She and her sister Lillian were ardent supporters of the suffragette movement, Lillian even being imprisoned for destroying public property. She was involved in psychic research, and after her husband's death, she claimed she maintained daily contact with him via seances.