Just in case anybody was thinking of sending parcels from an Italian post office and was utterly terrified after reading about my experiences, I thought I would post the end of the story here. Four of the boxes arrived within 3 days with most of the stuff intact (although one broken mug did lead to a whole other adventure).
The other one arrived almost 3 weeks later, when I had given up hope and was assuming that customs officials had taken umbrage at or a fancy to the bottles of wine that were carefully wrapped and included in the package. When I went to collect it at the post office, I was surprised to be given a completely different box, smaller than the one I posted and covered in Chronopost International labels. Some of the stuff was missing and a lot of it was broken. A lot of the things were newly wrapped in cardboard. A lot of the things were covered in red wine.
I'm assuming that since so many of the things were broken and since they had taken the trouble to repackage the whole lot that this was somehow the post office's fault and not mine, but there was no explanation, so who knows?
Incidentally, one of my friends posted boxes and boxes full of old clothes from Italy and wasn't even asked at the post office what was in the parcels.