Many women know that if they report the rape, it will not be prosecuted.

Many women know that if they report the rape, their rapist will make life hell for them.

I honestly don't know if you're just being obtuse, rude, or ignorant, but most people who have made any kind of study of the overall problem of rape and other forms of violence against women already know the reasons why rape isn't prosecuted, even when it's reported. When state budgets are cut and rape kits are no longer provided to victims unless they pay for them, there's virtually no evidence to prosecute with. When the rapist is the woman's husband or boyfriend, the father of her children, the provider of her sustenance, she's not able to prosecute. And yes, that's part of the rape/abuse syndrome: He uses his power over her as a means to coerce her into sex, and that is just as much real rape as the stranger in the dark alley. When police dismiss the charge as "a domestic dispute," women get the message pretty darn quick that nothing's going to happen even if they do level a charge.

Many women have so internalized their own blame even BEFORE they're assaulted, that if and when it finally does happen, they've already exonerated their assailant.

Many women don't even know that what they've experienced is real rape. Did he threaten to go out and find a prostitute if you didn't have sex with him, so you gave in rather than risk he'd get a disease and pass it along to you? That's coercion, and that's rape. Did he threaten to divorce you and take the kids away from you if you didn't have sex with him? That's rape. Did you have a few drinks and then couldn't seem to make it clear to him that you didn't really want to have sex with him but he did it anyway and how he's saying you told him he could? You weren't able to give consent if you were drunk, and that's real rape. Did he tell you you've had sex with him before and you might as well have sex with him again because no one would ever believe you were raped? It's still rape.

If the woman doesn't want to have sex and the man uses coercion, threats, or other forms of intimidation to have sex with her against her will, it's rape; but many women just plain don't know that, and so they've been raped and don't report it and it's not prosecuted but that doesn't make it any less rape.