What is the ruling of Islamic law regarding a wife who wishes to return to her poor husband, who does not pray regularly and smokes, despite her family's disapproval and her fear of losing her family if she returns to him, and her desire for the husband to come to her country to settle; must she obey her family or return to her husband?

Your husband has a greater right over you than your parents, and obeying him is more obligatory than obeying them. If his obedience conflicts with the obedience of others, you must prioritize obeying him. You are obligated to return to your husband's house. You must repent to Allah for lying about your grandmother's illness to leave his house.

Regarding financial support (nafaqah (definition)), if the husband does not provide his wife with the customary financial support, she has the right to seek a divorce. This is the view of the majority of scholars. Ibn al-Qayyim held that a woman is not permitted to annul the marriage due to her husband's insolvency unless the husband deceived her and showed himself to be wealthy when he was not. Sheikh Ibn Uthaymeen chose the view that if she married him knowing of his insolvency, there is no annulment, but he should not prevent her from working and earning. The preponderant view is that of the majority of scholars, which allows seeking divorce due to harm if the husband is unable to provide financial support.

It is the wife's right that her husband provide her with a dwelling separate from his family. If he does not provide this for her, she has the right to seek a divorce from him. In all of this, it is better and more preferable to be patient.