Diane earned an associate's degree in nursing at Fayetteville Technical Community College. Diane married Al, and together they have raised 3 children.

Diane is a registered nurse who has worked at Cape Fear Valley Medical Center, Orange Memorial Hospital, and the Fayetteville Children’s Clinic. She has also served on the Cape Fear Valley Hospital Board of Directors. Alongside her husband, she worked in government-contract work specializing in transportation operations on military bases in the southeast for over 30 years. Additionally, Diane remains active as a medical missionary, serving with medical teams in various countries.

Diane Wheatley was previously a member of the Cumberland County Board of Education. She was elected in 1994 and served 3 terms until 2002. She served as Chair during her first term and chaired the Facilities Committee the following year. In 2004, she was elected as a county commissioner and served 1 term until 2008. She ran in the 2012 election for state representative of District 45, but did not win. She was then elected in 2020 as a state representative in District 43. She chairs the Pension and Retirement Committee, and vice chairs the Education - K-12 and Education - Community Colleges Committees.