Does what the questioner feels—a continuous attachment to and thoughts about a person she has not spoken to, despite knowing he is married—count as a trial from Allah or a punishment, and does the Quranic verse, "For indeed, Allah leaves astray whom He wills and guides whom He wills," apply to it?

Allah Almighty's mercy upon His servants lifts the blame for error, so there is no sin in an unintentional glance or thought. However, one must avoid its causes. It is permissible to think about a righteous man and wish to marry him. There is no sin in accepting him as a husband if he proposes, and there is no injustice to his first wife if he practices polygyny, provided that one does not stipulate her divorce. Life is entirely a test; prosperity is a test for gratitude, and adversity is a test for patience. The verse: "Is he then, to whom the evil of his conduct is made fair-seeming, so that he considers it good? Verily, Allah leaves to stray whom He wills, and guides whom He wills" relates to Allah's power in guidance and misguidance. One must praise Allah for the blessing of faith and steadfastness in His obedience, and frequently remember Him.