Born in Millstadt, Illinois, she attended the Academy of Notre Dame in Belleville, Illinois. She was received into the School Sisters of Notre Dame novitiate in 1957 and given the name Richard Maureen in honor of her father. She professed first vows in 1958 and final vows in 1964. She later returned to her baptismal name.

Sister Deanne ministered in Catholic education for more than 40 years. In the Archdiocese of St. Louis, she taught at St. Aloysius School in St. Louis. She also taught at schools in Jefferson City, Missouri, in Belleville, Illinois, and in California. She was a principal in Caseyville and Belleville, Illinois, and in California. She served a five-year term as an associate superintendent of schools for the Diocese of Belleville as well as director of childhood education in that diocese. For two years, she was the coordinator of the Education Council for the former St. Louis Province. In 2000, she became development director for Sister Thea Bowman School in East St. Louis and Holy Rosary School in Fairmount City, Illinois. In 2006, she was appointed director of Notre Dame Tutorial/Learning Center at Ripa in south St. Louis County. She later ministered as a driver at the Ripa complex and gave volunteer service. In 2017 she moved to Anna House.

Sister Deanne enjoyed fishing, golfing, camping and hiking. She was an avid St. Louis Cardinals fan. She loved music and played a tuba in her earlier years.

Survivors include a brother, Richard Stratmann, and sister, Maureen Hobbs, of Nashville, Illinois. Burial was in the Sancta Maria in Ripa cemetery. A memorial Mass will be celebrated at a future date.