The United States Air Force does not restrict personal relationships with unaffiliated civilians, but it does have strict rules against fraternization amongst members. This especially applies to relationships between officers and enlisted members.
The Air Force defines the guidelines of professional and unprofessional relationships in regulation number 36-2909. It restricts any unprofessional relationships between officers and enlisted members, as well as civilian employees of the Department of Defense or other entities affiliated with the Air Force. The Uniform Code of Military Justice defines fraternization as any romantic relationship, sexual or not, between an officer and an enlisted member, regardless of gender or sexual orientation. Fraternization usually only applies to officers, but it does not prohibit an officer from being married to an enlisted member, as long as the relationship does not hinder the integrity of the Air Force.