Book about a college professor who marries an aspiring writing student. He writes books, she edits and helps, he gets famous and has affairs at writers retreats. She is resentful but stuck. He wins a book award but cannot claim it, dies I think. She realizes that she has been rewriting his novels while editing and feels cheated

"The Wife" by Meg Wolitzer
"A tall, fair, "slender, hygienic Smith girl," Joan goes against type when she leaps into bed with her dark-haired, Jewish, married creative-writing professor, and their affair, based in large part on Joe's admiration for her high-caliber short stories, promptly leads to their mutual banishment from academia and Joe's divorce. They move to New York and get married. Joe starts writing, and Joan secures a job at the publisher that publishes the novel that jump-starts Joe's stellar career. Joan then quits her job to devote herself to husband and children, holding steady against the turbulence of Joe's unremitting self-absorption and conspicuous philandering. Forty years later, Joe wins the much-coveted Helsinki Award, and Joan decides that she's had enough of their smothering marriage and its scandalous secret. That's the foundation for what becomes a diabolically smart and funny assault against the literary establishment and the tacit assumption that only men can write the Great American Novel. As Joan recounts the misery she and her fellow writers' wives endure, popular and shrewd novelist Wolitzer choreographs her ire into kung-fu precision moves to zap our every notion about gender and status, creativity and fame, individuality and marriage, deftly exposing the injustice, sorrow, and sheer absurdity of it all" (From Booklist)