I always refer to the same gender partner as wife or husband... but even living in MA, where we are (somewhat) ahead in most social issues, even I live in a bubble. Once in awhile I hear one of my (non-cycling, non-therapist) friends say something, not really knowing that it's offensive. I always correct them.
Before I went to grad school, I always defended gay rights, but after the experience of becoming friends with many gays and lesbians, I would consider myself an ally. I would hope that a gay or lesbian client would feel comfortable seeing me as a therapist, even though I am not gay.
And Murienn, you are right about the military. My son in the Marines doesn't see this any differently than my son who lives here.