Tā / fā xiàn / duì fāng / yǐ jīng / yí qíng bié liàn / jué dìng / jié shù / zhè / duàn / gǎn qíng

她发现对方已经移情别恋，决定结束这段感情。

She realized that the other person had fallen for someone else and decided to end the relationship.