What is the ruling on one who curses his wife or fiancée and describes her as wicked and insolent, and is it obligatory to continue the relationship with him?

If these words were uttered before marriage, this indicates poor character and stinginess in the suitor, and it is recommended to reject this engagement because your life will be difficult, and Allah will compensate you with someone better than him. And know that the Messenger of Allah, peace and blessings be upon him, said: "If there comes to you one whose religion and character you are pleased with, then marry [your daughters] to him. If you do not do so, there will be tribulation on earth and widespread corruption."

This suitor is a stranger to you until the correct marriage contract is concluded. Therefore, it is not permissible for you to allow him to look at you, or to be alone with you, or to speak with him except out of necessity. If the correct contract has been concluded, then his statement "You are a wicked woman" is potentially an accusation of fornication, so he must repent to Allah.