The phrase "break one's heart" denotes a deeply painful and hurtful feeling. Although there are numerous synonyms, the opposite or antonyms of this phrase could mean positive or neutral emotions. Rather than breaking someone's heart, we can use terms such as "mend someone's heart" or "heal someone's heart." If someone makes your heart burst with happiness, then that means they make you overjoyed. Furthermore, "fill someone's heart" or "warm someone's heart" means to offer love, kindness or caring. Some other antonyms could be "bring joy," "make happy," "give fulfillment," or "lift someone's spirits.
