Their constant arguing is gall and wormwood to me.
gall and wormwood
idiombitterness and resentment
Origin
disputed originFrom Deuteronomy 29:18 of the King James Bible.
The unfair decision felt like gall and wormwood, leaving him with a deep sense of resentment toward his former partners.
The memory of his betrayal remained gall and wormwood, a bitter reminder of the trust he had once placed in his closest friend.