While I'm definitely aware of the "Ronnie" nickname (I, too, dislike it), the two Veronicas I went to high school with went by completely different nicknames. One was "Vero" (pronounced VEH-roh, with a trilled R - she was of Argentine descent), and the other was "Veva"/"Viva" (I'm not sure how she acquired that nickname, though).
So it is definitely possible to avoid the dreaded Ronnie.
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