Occasionally I say “Oh my gawd!” (most often after hearing somebody vomit up Pascal’s Wager). Sometimes I say it in the presence of believers. Sometimes they point and exclaim “Aha! You said ‘oh my gawd’! You must, deep down, believe in gawd!”
My response is usually to burn them with my gaze and explain that if I stub my toe going for a midnight snack I generally say “Fuck!” It doesn’t mean I want to have sex.