What is the ruling regarding a married woman whose heart is attached to another man, and she has failed to rid herself of this feeling? Should she inform her husband of this, despite her fear of destroying his life?

It is advised to be patient and content with Allah's decree, to avert one's gaze from the foreign man, and not to inform the husband about this or ask him for a divorce. This is based on the Hadith: "Any woman who asks her husband for a divorce without any strong reason, the scent of Paradise will be forbidden to her." Allah knows what is best for a person, and He may place much good in what is disliked. If cohabitation becomes impossible and there is a fear of falling into sin, it is permissible to request a divorce without informing the husband about one's attachment to another. If the husband refuses to grant a divorce, it is permissible to seek a Khul' (dissolution of marriage initiated by the wife) by returning the dowry or part of it, as Allah Almighty says: "But if you fear that they will not uphold the limits of Allah, then there is no blame upon either of them concerning what she gives up to free herself."