I travel all the time in Italy without problems. I spent a few months sketching and taking pictures around Rome without any sort of harassment. My partner and I spend at least a week in Rome each year, granted we are an interesting looking couple, but no problems.
I would highly suggest finding a hotel with a well lit entrance near the centro storico and just try and ignore cat calls and come ons.
I would also avoid the 64 and 66 buses unless you are feeling like being felt up.
Seriously, Rome is a city I have no problem in-- maybe its because Romans think I'm Italian?
lala