Does the fact that the Prophet, peace and blessings be upon him, did not marry another woman during the lifetime of Khadijah, may Allah be pleased with her, mean that whoever marries another woman is not faithful to his first wife?

The Prophet, peace and blessings be upon him, did not marry anyone else while Khadijah, may Allah be pleased with her, was alive, out of loyalty and honor to her. However, marrying another wife does not imply a lack of loyalty. The Prophet, peace and blessings be upon him, married other women after Khadijah and was the most loyal and benevolent of people to his wives. He also married other women while Aisha, may Allah be pleased with her, was alive, despite his intense love for her, and this did not diminish her status in his eyes.