I was flying in FC on an AA flt. from LAS to CLT. The seat config. per row, 2 seats (middle aisle) 2seats. I was seated in a window seat, a woman was next to me and her husband in the aisle seat in the same row. This plane had no overhead monitors, so the FA had to give the safety demonstration, the woman briefly said something to her husband (not loudly); the FA approached her: "do you want the plane to return to the gate to have you ejected?" That FA did pre-departure drinks, she had "bubbly stuff", after the incident, the FA came through to take drink orders once airborne, she ask for another "bubbly" drink, FA to woman: you can't have any more alcohol. That FA on a "power trip", disappeared to Y being replaced by a different one from Y.