My hunch is that it's some kind of nickname for
Giuseppa, though I'm Italian and have never heard it withered.
"We have to live without sympathy, don't we? That's impossible of course. We act it to one another, all this hardness; but we aren't like that really, I mean...one can't be out in the cold all the time; one has to come in from the cold...d'you see what I mean?”
John LeCarré