The phrase "ate one's heart out" is often associated with feelings of jealousy or deep longing. This expression is commonly used when someone is envious or want something very badly. However, there are numerous antonyms for this phrase that convey the opposite meaning. Words such as satisfied, content, and fulfilled are some antonyms that can be used instead of "ate one's heart out". These words suggest a feeling of happiness and completeness and imply that one's desires have been fulfilled. So if you want to express contentment or satisfaction, using one of these antonyms will help convey your intended meaning.