To acquaintances and people I don't know, I refer to my wife as "my beloved" or "my beloved wife" or "my wife". To friends I use her first name. I could call work colleagues "partners", but would never call them "beloved(s)". If I do not know the relation status of someone I use "your significant other".
I know people who register their wife in their mobile phone contact list or BMW memory buttons as "The Boss".
