All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
If the situation is as mentioned in the question that the husband abuses his wife physically and threatens to beat her, kicks her and abuses her verbally using obscene words and other details which you mentioned, then this is a clear injustice and his behavior contradicts the order of Allaah to the husbands to treat their wives honorably. Allaah Says (what means): {And live with them in kindness.}[Quran 4:19]
In fact, each of the above misbehavior of the husband allows the wife to ask for divorce but we do not advise her to hasten to ask for divorce unless she performs the Istikhaarah prayer and seeks the advice of wise people from her relatives because it might be more beneficial for her to be patient with her husband. For more benefit on the cases when a wife is permitted to ask for divorce, please refer to Fatwa 88408.
However, we advise the spouse to have mutual understanding and both of them should know the rights of each other and fulfill them as much as they can. Allaah Says (what means): {And due to the wives is similar to what is expected of them, according to what is reasonable.}[Quran 2:228] For more benefit on the rights of the spouses towards each other, please refer to Fataawa 85308 and 83157.
Finally, the two following matters should be mentioned:
1- It is not permissible for the wife to accuse her husband of watching pornographic films without clear evidence. This is a bad assumption (suspicion) and this is forbidden.
2- It is an obligation to advise the brother of this wife who apostated from Islam and remind him about the seriousness of this matter hoping that he will take heed and re-embrace Islam. For more benefit, please refer to Fatwa 87672.
Allaah Knows best.