What is the ruling of Islamic law on the marriage of a man and a woman who committed Zina together, and will Allah forgive them if they do not marry, and what are the consequences if the girl refuses to marry him due to family pressure after her repentance?

Adultery is a grave crime forbidden by Allah, who described it as an abomination and an evil way. Its sin is not expiated except by sincere repentance. Marriage to the person with whom the adultery was committed is not a condition for repentance; rather, she must first repent if he wishes to marry her. Furthermore, the execution of the prescribed punishment (حد) does not nullify or diminish repentance. The prescribed punishment is an expiation for the one upon whom it is inflicted. If Allah conceals the sin of the transgressor, then his matter is with Allah, glory be to Him. It is better for one whose sin Allah has concealed to conceal it himself and not confess it, for Allah conceals the sins of His believing servant in this world and forgives him on the Day of Judgment.