This is often witnessed in a relationship in which the couples are very comfortable with each other, have been together for months if not years, or a crumbling relationship, or a combination of the set above.
However, it can also apply to close friends or family with similar forms of ignorance and douche-baggery.
Jim: Hey, you didn't pick up last night. What were you doing?
Jill: Stop worrying, you pussy. I was painting my nails and playing your CoD file.
Jim: I told you not to touch my 360! Ever! Go make me a sandwich for that, bitch.
Jill: Well that sandwich won't fix itself until you fix the God Damn Bathroom.
-- Later --
Jill: God damn, Jill is giving me the "Boyfriend Syndrome".
Jack: What? Sorry, bro, I didn't catch watch you said. Is that chick was eyeing me over there?