What is the Sharīʿah ruling concerning a husband who treats his wife with cruelty, beatings, and humiliation, watches pornography, engages in relationships with other women, seizes his wife's salary, refuses to spend on her, seeks to humiliate her, and demands that she serve his family? And is it permissible for the wife to seek a divorce from him in this situation?

Your husband is unjust, abusive in your marital relationship, and transgresses the limits of Allah. Advise him gently and clarify his duties and your rights to him, and the impermissibility of the evil acts he commits. Try to guide him to repentance and rectitude. If that does not help, then weigh the harm of divorce against the harm of remaining with him, and choose the lesser of the two harms.