Is the wife considered sinful for leaving her home, where her husband, afflicted with schizophrenia, resides, without his permission, fearing harm to herself, and for cutting off communication with him? And is her request for separation legitimate?

It is not obligatory to inform the suitor about a psychological illness unless it reaches the point of insanity. It is permissible for a woman to leave her husband's house without his permission for a legitimate excuse. A woman has the right to seek divorce due to clear harm. Communicating with a sick husband is part of good companionship, but it is not obligatory if his condition worsens and the illness overwhelms him.