Is it permissible for my fiancée to remove her hijab at work, under the pretext that her manager refuses her working with it on, and that she is the sole provider for her family who depend entirely on her to secure their essential needs, acting on the principle of "necessities permit the forbidden" and "But whoever is forced, neither desiring [it] nor transgressing, then there is no sin upon him. Indeed, Allah is Forgiving and Merciful"?

A woman covering her hair is obligatory, and no one should be obeyed in a matter that disobeys the Creator. However, if a woman is compelled to do so in her work, then necessity is assessed according to its extent. Necessity is defined as that which makes it highly probable that destruction will occur, or an unbearable hardship, or an inability to achieve the minimum standard of living for the poor, or inflicting such a condition upon those whose support is obligatory. If the necessity ceases or an alternative is found, the ruling is lifted, and the matter reverts to its original state, which is absolute prohibition. A woman must assess her situation to determine if it reaches the level of necessity, and consider whether it is possible to find another permissible job that meets her needs and suffices for her and those she supports, for "whoever fears Allah, He will make for him a way out." If she is permitted to remain in her job due to necessity, she must strive to find another job. If her parents are poor and unable to earn, she is obliged to earn enough to suffice them. As for non-parents from her mahram relatives, earning to support them is not obligatory, but it is commendable to spend on them to maintain ties of kinship.