How can a young man complete his marriage despite his mother's refusal to attend the engagement, and his father owning two houses that are unsuitable for living, which forced him to accept his fiancée's father's offer of free rent in one of his houses?

The fundamental principle is a mother's affection for her son. What has been mentioned about the mother's harshness and her inciting the brothers against him is unusual and contrary to this principle. However, honoring her is obligatory in all circumstances. We advise seeking the reason for her coldness and supplicating to Allah Almighty to earn her رضا (contentment/pleasure).

A mother's opposition to her son marrying a girl does not warrant obedience, as obedience to parents is conditional. The primary approach should be to try and convince her.

Housing is a right for the wife, and there is no harm if a father favors one of his children with housing due to his need for it.