Anata-tachi ni Suterareta Watashi wa, Youyaku Shiawase ni Nare Sou desu

Ariane, a young girl born under the strong protection of the spirits, grew up with Lionel, the son of a duke who she had known since childhood. They vowed to marry each other and lived peaceful, happy lives together. But one day, her father, the count, forced her into an unwanted engagement with the second prince and confined her to their mansion. Believing she would be reunited with Lionel, Ariane endured her loneliness, but eventually she was deprived of the spirits' protection and was treated coldly by her family, pushing her to the brink both physically and mentally. Meanwhile, Lionel secretly began plotting to win back his beloved Ariane...

(Source: Kadokawa, translated)