I knew you will show up.
To clarify my post, beating the wife and hurting her as a force into sex is a crime, and she has the right to go to the court and sue him. If she refused because of being tired for an example while he didn't accept her wishes, and forced her into sex without causing any damages to her body but mentally is not considered a crime in the Islamic law. Not to mention that some women will find harder to speak out fearing divorce. That being said, the Muslim wife clearly knows/aware that she is wrong, when she rejects her husband request, because as you know she will be cursed by the angels if she does. Therefore, the word "marital rape" is a recent concept and rare in our community.