I Only Need Our Child, Your Grace

Blair Ardel was forced into a political marriage with the cold Duke Herdin Delmarque. Though she loved her husband and treasured their son, her marriage ended in betrayal when she was murdered one night. But instead of dying, Blair awakens three years in the past. Determined to reunite with her son and uncover the truth behind her murder, she agrees to marry Herdin once more, this time through a contract marriage on her own terms. As secrets, conspiracies, and feelings begin to resurface, Blair must decide whether fate can be changed... or if she is doomed to lose everything again.

(Source: Webtoon Entertainment)