Bridgid Kathleen MacSeoin was born in 1957 in Riverside, California. She enlisted in December 1981 and completed her basic training at Lackland Air Force Base in Texas. While still at Lackland, she completed tech school in 1982. In May 1985, she trained for emergency management at Lowery Air Force Base in Colorado.

By August 1985 she was stationed at the Royal Air Force Bentwaters in Suffolk, England where she remained until March 1989 when she was then stationed at Royal Air Force Mildenhall. At Mildenhall she worked in First Disaster Prep. During this time she was deployed for a month aboard the MV Green Ridge Merchant Marine Ammunition Ship. Macseoin was then deployed to Norway from 1992-1994 where she worked in regional logistics. When she returned to Mildenhall, she began to work in Readiness Tech in which she would continue until February 1998, except for a three month deployment working in recovery operations for Operation Southern Watch at Dhahran, Saudia Arabia following the Khobar Towers bombing of June 1996.

In 1998, she left Mildenhall for Bolling Air Force Base in Washington DC where she would stay for two years before returning to RAF Mildenhall. Here she worked at Mildenhall's Headquarters Air Refueling Wing where she was a superintendent of wing exercises. During this period she was deployed to Prince Sultan Air Base in Al Karj, Saudia Arabia for Operation Enduring Freedom where she worked in the Combined Air Operation Center from November 2001 until March 2002. In June 2003, MacSeoin returned to the United States to Scott Air Force Base in Illinois where she worked in Headquarters Air Mobility Command until she retired in September 2006.