Khadija the Great

Khadijah or Khadīja bint Khuwaylid (Arabic: خديجة بنت خويلد‎‎) or Khadīja al-Kubra (Khadija the Great) (555–620) was the first wife of the Islamic prophet Muhammad. She is commonly regarded by Muslims as the Mother of the Believers (i.e., Muslims), and was the first person to convert to Islam for Muhammad's proclamation of faith.

Khadija in "Departures"
Mouamet's marriage to Khadija ended when he forsook the things of the world to join the monastery of Ir-Ruhaiyeh. In later years, he occasionally wondered if she still lived, as she was a good deal older than he. With very human vanity, he wondered if she ever thought of him. With his own characteristic honesty, he doubted it. The marriage had been arranged. It was not her first. Probably it would not have been her last, either.

Literary comment
Mouamet's wife isn't named in the text, but the description matches Khadija.