Yo Kass answered
To translate the phrase 'my beautiful girlfriend' literally, you waould say 'mia bella ragazza'. The Italian word for beauty is bellezza and most Italians refer to their girlfriend as their ragazza (which also just means 'girl'), although the use of fidanzata (girlfriend), amore (love), fiamma (flame), or even the anglo-export 'partner' are all fairly common references to one's female love interest.
Other Nicknames
As with any language, the number of nicknames you can give your girlfriend are only limited by your imagination. Scrolling through some Italian internet forums, I've come across suggestions of everything ranging from the rather cute coccola (meaning cuddle) through to the sexually frustrated mutande di ferro (literally: Underpants of steel).
Other classic ideas are stellina (little star), bambola (doll) or tesoro (treasure). A popular trend in Italy is to call a loved one after a favourite food, especially something sweet-tasting like zuccherina (sugar lump), but this can also venture into the realm of the savoury such as patatina (potato chip), polpetta (meatball), gnochetta (a type of dumpling) or even cipola (onion).
Whatever you decide on, the key to any nickname that you give your girlfriend is that it is unique, represents your relationship, and means something special to both of you.
Other Nicknames
As with any language, the number of nicknames you can give your girlfriend are only limited by your imagination. Scrolling through some Italian internet forums, I've come across suggestions of everything ranging from the rather cute coccola (meaning cuddle) through to the sexually frustrated mutande di ferro (literally: Underpants of steel).
Other classic ideas are stellina (little star), bambola (doll) or tesoro (treasure). A popular trend in Italy is to call a loved one after a favourite food, especially something sweet-tasting like zuccherina (sugar lump), but this can also venture into the realm of the savoury such as patatina (potato chip), polpetta (meatball), gnochetta (a type of dumpling) or even cipola (onion).
Whatever you decide on, the key to any nickname that you give your girlfriend is that it is unique, represents your relationship, and means something special to both of you.