Life was no easier back in England. Many people refused to associate with Shelley because of her elopement with Percy a decade earlier. (People in 19th century England did not forget things easily.) Still grieving the loss of Percy, Shelley hoped to assuage her pain and earn a living by writing a biography of her late husband. Shelley's father Timothy blocked her efforts, however, by threatening to cut off support to her son Percy Florence if she dared publish the details of his son's life. Timothy Shelley had not forgiven his son for his radical, unconventional lifestyle, and did not want history to remember him as he was.
Shelley got to work instead on another science fiction novel entitled The Last Man. Just as Frankenstein gave birth to centuries of rip-offs and remakes, The Last Man introduced the popular device of mankind fighting for its very existence, as war and plague threaten to wipe it out. She was also able to circumvent Timothy Shelley's prohibition on writing about his son by basing the fictional character of Adrian, Earl of Windsor on an idealized version of Percy Bysshe Shelley.
Her novel was a success, but Shelley was horribly lonely. "The last man! Yes I may well describe that solitary being's feelings, feeling myself as the last relic of a beloved race, my companions extinct before me," she wrote in her journal. "At the age of twenty-six I am in the condition of an aged person--all my old friends are gone ... & my heart fails when I think by how few ties I hold to the world." Men were interested in Shelley, but she refused to marry again. Her emotional energy went toward taking care of her son, Percy Florence, and her father.
Writing saved her. Though she never again wrote anything as popular as Frankenstein, Shelley worked diligently on books and articles for the remainder of her life. She published the (mostly unsuccessful) novel The Fortunes of Perkin Warbeck in 1830, followed by the novels Lodore in 1835 and Falkner in 1837. She also wrote dozens of essays and reviews. Timothy Shelley eventually relented and allowed her to publish an anthology of Percy Shelley's work, provided that the collection not contain any biographical information about the poet. Shelley got around this clause by writing introductory notes to the poems. She published the collected poems of Shelley in November 1839, followed by a collection of Shelley's essays and other writing.
Problems continued to hound Shelley, but she faced them with grit and courage. In 1841 a man claiming to be Lord Byron's son threatened to publish letters allegedly written by Mary and Percy Shelley unless Mary Shelley paid him off. She sought and won a court injunction to prevent him from doing so. By the late 1840s, Shelley was experiencing the first symptoms of the brain tumor that eventually took her life. In December 1850 her right leg went numb, and she had trouble talking. Within a month she was almost completely paralyzed. Mary Wollstonecraft Shelley died 1 February 1851 at her home in London. She was buried between her parents, the two people who taught her by example never to compromise who she was.