Trueman was born in Glenwood, Minnesota, and educated at the Kahler School of Nursing in Rochester, Minnesota, and worked as a registered nurse. She married Kenneth Trueman, a physician and son of Walter Harley Trueman.[2] She was the President of the Junior League of Winnipeg from 1951–52.[3] Trueman served as a city councillor in Winnipeg from 1968 to 1969.[4]
She was elected to the Manitoba legislature in the provincial election of 1969, defeating New Democrat Una Decter by 304 votes in the Winnipeg riding of Fort Rouge. The NDP won this election, and Trueman sat in the opposition benches, where she was the health and welfare critic.[5] In 1971, she was one of only two opposition MLAs to support the NDP government in amalgamating the city of Winnipeg.