Marianne was born in the small town of Ashland, Kansas, near the Santa Fe Trail, where her father and two brothers consecutively practiced dentistry. She grew up in the middle of ranches, wheat fields, and Indian country.
She attended The Wichita State University, and upon graduating in 1973, she immediately moved to Loveland, Colorado. She has practiced dental hygiene in Denver, Estes Park, Elk City, Oklahoma, Amarillo, Texas, Manhattan and Dodge City, Kansas, and in her hometown, working with both of her brothers.