Marianne Shenefelt was born in Denver, Colorado, and grew up on a ranch northeast of Cheyenne, Wyoming. She married Francis (Frank) T. Shenefelt at Cheyenne in 1968, and they have lived in Cheyenne since that time. They are the parents of one daughter, Holly. Holly is a Major in the United States Air Force and is the Deputy Commander of the 84th Civil Support Team, attached to the Wyoming Army National Guard, Cheyenne. Marianne is retired from the State of Wyoming.
Marianne was initiated into Burns Chapter No. 47, Burns, Wyoming, in 1979, with her sister, Louise. She has served as Worthy Matron three times. Holly is a member of Burns Chapter, making the fifth generation of Eastern Star in Marianne's family. Marianne is a dual member with Harmony Chapter #53, Cheyenne, Wyoming.
In 1998, Marianne was appointed by Worthy Grand Matron, Sister Rebecca Dolling to serve as Grand Representative of Manitoba in Wyoming and in 2000, she was appointed to serve as Grand Esther by Worthy Grand Matron, Patricia Harwood and Worthy Grand Patron, Chuck Gragg. Marianne was elected Associate Grand Conductress in 2001 and installed as Worthy Grand Matron, of the Grand Chapter of Wyoming in 2004. In 2005, she and Worthy Grand Patron, Larry Farnham presided at the 108th Grand Chapter of Wyoming’s "A Circle of Friendship" Session.
Sister Marianne was appointed to serve on the 2006-2009 Heart Committee of the General Grand Chapter by Most Worthy Grand Matron, Sister Barbara Benton and Most Worthy Grand Patron, Brother William Owen.
In November of 2009, at the GGC 46th Triennial Assembly in Tulsa, Oklahoma, Sister Marianne was elected Right Worthy Associate Grand Conductress of the General Grand Chapter.