What are my rights as a wife concerning my husband, and am I obligated to serve his family and visit them despite their repeated abuse towards me and my daughter, and is my husband entitled to give a large portion of our salaries to his family, given that he does not contribute to household expenses and I bear them entirely?

The harm inflicted upon you and your daughter by your husband's family through slander, denigration, and backbiting is forbidden, as it constitutes harming a Muslim, and Allah has warned those who do so of woe. Denigrating a person's appearance and creation is prohibited because it is a disparagement of Allah's creation, and disparaging the craftsmanship ultimately reflects back on the Creator. Their prayers (curses) against the young daughter are sinful and an act of aggression.

Your husband's silence regarding his family's actions is detrimental and impermissible; it is his duty to stop them. Your husband's mistreatment and aggression towards you are impermissible, as they contradict Allah's command to live together in kindness.

Your husband's swearing by divorce and declaring things unlawful is impermissible and is considered an oath of the wicked. If he repeats his oath and breaks it three times, the matter must be presented to scholars or a Shariah court.

Serving your husband's family is not obligatory for you; rather, it is a voluntary act, and your husband is not allowed to demand it as an obligation. Your husband's family are not your blood relatives ( رحم ) whom you are obliged to maintain ties with, but they do have rights due to the marital relationship. It is permissible to shun them if they do not cease their harm.

What your husband gives to his family from his wealth is his right, and you are not permitted to object to it as long as he does not fall short in providing for you. Your money and salary are your own, and you are not obliged to spend from them on the household, as financial support is the husband's obligation.