My Brother Snapped When My Engagement Was Called Off

Lizzy, raised as the daughter of a wealthy earl's family, became engaged to a marquess house on the brink of ruin when she was young. Although it was not a marriage born of love, Lizzy devoted herself to various studies so that she could restore the marquess house and protect the people living in its territory. However, one day at a party attended by people of her generation, she is declared by her fiancé to be breaking off their engagement.