If you eat the same food all the time, your body will be undernourished and eventually you will plump up or starve.
As Shakespeare said, "If music be the food of love." Listen to music from a wide variety of countries, time periods, composers, styles, moods and performers. You will surprised at the differences and the similarities between kinds of music. I once heard folk music from a river people of Laos that resembled Cajun music! It had the rhythms of the river in it--different rivers but similarly rolling along!
Allow yourself to discover great sources of musical "nourishment." If you compose, do not be afraid to listen to the music of others. I believe that if you are worried about keeping your individual "voice", then your knowledge of your own self is what is lacking. Listening to music created by other composers will not make you personality-less or a copycat. No one can rob you of what really lies within you except yourself. Explore and absorb all kinds of music into your own vocabulary and make it your OWN.
There's a feast out there!