Good question, Nichola. Accounts of violence suffered - both physical and psychological - are clearly OK, and in fact a mainstay of the 'traumemoir' Medium subgenre.

When it comes to fiction, though, you may be presenting such acts from the viewpoint of the perpetrators and their supporters. But I would assume that the fact it is fiction would itself explain and justify that. If a fictional character expresses and acts on unacceptably violent thoughts, that is not, as you say, an espousal of such acts by the author, and in fact would often - as in your case - be quite the opposite, instead siding with the victim of the violence, and encouraging the readers to do the same. Or even to understand the psychological damage causing the perpetrator to act as they do.

I should think you're safe.