Gabrielle ( Renee O'Connor ) becomes Xena 's greatest friend , her initial naive helps to balance Xena and helps her in seeing and fighting for the greater good . . Xena is accompanied by Gabrielle ( played by Renee O'Connor ) , who during the series changes from a simple farm girl into an amazon warrior and Xena 's greatest ally ; her initial naÃ vetÃ helps to balance Xena and assists her in recognizing and pursuing the `` greater good '' .