But her work on the first Chinese translation of the complex, stream-of-consciousness James Joyce opus about an Irish family paid off when the first print run of 8,000 sold out within weeks of hitting store shelves in December.
"It was dull and depressing during the first two years," the 41-year-old literature professor at Shanghai's Fudan University told Reuters. "I was also starting to have doubts about the project because I'd spent two years on the book but not a single word was translated."
A seasoned translator of books about culture and identity, Dai, who taught herself English, first started reading Finnegans Wake - a massive experimental novel notorious for its difficulty and convoluted prose - while at university.
Research into Joyce as part of her doctorate followed, and though her academic advisor recommended Dai translate the book when she successfully defended her dissertation, its difficulty scared her off. A later invitation from a publisher she knew, though, proved irresistible, and she began.
Joyce's frequent use of made-up words sent her poring over multiple versions of English dictionaries, making notes on every page of the book. Two years of preparation were followed by six of actual translation - in between teaching classes at the university as well as fulfilling other academic duties.
There were also obstacles at home.
"I have to take care of my young son. What's more, my family - especially my husband - didn't support the project," Dai said.
"He thought that despite the time and energy I needed to put into it, it would not make much money because the book is too difficult for an average person."
Despite everything, Dai found satisfaction in her labors.
"I enjoyed the moment when I finally found the exact and appropriate translation of a word or a sentence. I now know more about Joyce and the Irish culture," she said. "I think Joyce as a person was difficult to get along with for ordinary people, but I think he is a great person and a talented one."
Microbloggers on Sina Weibo, the Chinese equivalent of Twitter, lavished more praise on Dai's achievement than they did on the book itself.
"Oh my God! How admirable Dai Congrong is! How was she able to continue translating one book for eight years?" wrote Yao Zhenghua.
When her publisher told her that the 755-page book had sold out in three weeks, she was pleased but astonished.
"Actually, the news was so unbelievable that I first thought they were wrong," she said. "It shows our people are thirsty for culture and knowledge."
Dai's toil remains far from over, since she has actually translated only the first third of the book. Two more volumes are planned.
"Even I don't know how long it will take to finish," she said. "But I will do my best."
(Reporting by Shanghai newsroom and Kazunori Takada, writing by Elaine Lies, editing by Paul Casciato)