Food poisoning is no joke. I feel for her.
Been in the same shape more than once, fortunately at home and not an airplane.
Not a damn thing to be done, except an IV, which my wife did for me once. Nothing quite like sitting on the pot with an IV, lol.
Waiting to clear customs without blowing chunks out of both ends seemed like an eternity.
Handy tip: Never have a wicker or mesh wastebasket in the bathroom.