Is the woman who seeks a divorce during the engagement period sinful for not feeling capable of bearing the responsibility of marriage?

A wife's request for divorce is permissible if there is a compelling reason for it, such as her hatred for her husband. The prohibition against a woman seeking divorce applies when there is no valid reason. There is no difference in the ruling whether the marriage has been consummated or not. It is advised to deliberate and not rush into seeking a divorce, to consult with wise individuals, and to perform Istikhara (prayer for guidance) before proceeding.