What is the ruling on a wife who tells her husband: "May Allah forbid me to you," and then leaves for her family's house and later returns?

If the wife says, "May Allah forbid you to me" or "May Allah make you unlawful to me," this is a supplication that carries no legal consequence, but she should not say it. However, if she says, "You are unlawful to me" or "You are forbidden," this is not permissible, and she must offer an expiation for a broken oath, because whoever forbids what Allah has made lawful must offer expiation for an oath. Dhihar (a form of divorce where a husband declares his wife to be like his mother) does not apply to women. So, if a woman forbids her husband, she must offer an expiation for an oath: feeding ten poor persons, or clothing them, or freeing a slave. If she is unable to do so, then fasting for three days.