The antonyms for the phrase "changed sides" could include words and phrases such as loyalty, consistency, steadfastness, and allegiance. These terms suggest a sense of commitment and dedication to one's beliefs or values, without wavering or flipping to the opposite side. Other antonyms could include words such as unmoved, unswayed, and unconverted, as these terms suggest a lack of change or movement from one position to another. In contrast, the phrase "changed sides" implies a shift in perspective or allegiances, which can have both positive and negative connotations depending on the context in which it is used.