Tsuihou Sareta Seijo wa, Suterareta Mori de Wakeari Biseinen wo Hirou: Ima no Seikatsu ga Tanoshii node, Mukae ni Korarete mo Kaeritaku Arimasen!

Leah is the guardian saint of her kingdom, and has been bullied by her older sister, Priscilla, for as long as she can remember. Despite the constant beratement, she has been using her powers to heal the townspeople, fight with monsters, and protect the kingdom. However, one day, Priscilla made her final move. She convinced the prince to call off the holy engagement, claiming that she herself is the true guardian saint, and forced Leah into exile. Having been sent to the forest of illusion to carry out her exile, it was no different than a death sentence. However, that changed in an instant as she comes across a young prince from the neighboring kingdom who is in serious need of healing! (Source: MangaPlaza)