The phrase "wert sweet on" is an idiomatic expression that describes a person's infatuation or attraction to someone or something. The antonyms for this phrase would be disinterest, dislike, or aversion. Disinterest refers to the lack of interest or enthusiasm towards something or someone. Dislike, on the other hand, is a feeling of distaste or antipathy towards someone or something. Aversion is an extreme form of dislike, where a person has a strong feeling of repulsion or hatred. These antonyms suggest a negative sentiment towards the object of affection, indicating a lack of fondness, attraction, or love.