Her name was Nancy Witcher Langhorne. She is also reputed to have referred to the soldiers who took part in the invasion of Italy as D-Day Dodgers

If her Ladyship did, indeed, say this ... I say SHAME!
This hits a very sore spot for me .. I had relatives in the 8th Army and an uncle who was among the men who fought in the three battles for the Kasserine Pass and a neighbor's son was killed at the battle of Monte Cassino. Hell on earth found itself a fact in those places. Too many brave decent American and British boys went through that hell called The Italian Campaign to ever be described as Lady Astor allegedly did.
For more info in UK and world wide, consult "The Oxford Companion to World War II" published in 1995 by Oxford Press -- in US the ISBN is 0-19-866225-4
Wow