Valentine began her career in 2003 as a correctional officer at Kentucky State Reformatory. She promoted through security to the rank of captain in 2008, serving as the dayshift supervisor with a complement of 176 staff members. In 2010 she promoted to unit administrator I where she worked in reentry, the Correctional Psychiatric Treatment Unit (CPTU) and unit B. She also served as the institutional public information officer, equal opportunity coordinator and the veteran's certifying official.

A 2009 graduate of the Commissioner's Executive Leadership Program, Valentine is a certified correctional program checklist auditor. She is also a United States Army veteran who served in several stateside and overseas posts.