What should I do about my marriage to a man whose intimacy I reject, and his refusal to divorce me, while I remain in a relationship with someone else? Is my situation a result of accumulated psychological issues or a lack of religious devotion and chastity?

You must initiate repentance and sever the relationship with this corrupt young man who is spoiling your relationship with your husband. You must avoid negligence or procrastination in this matter. You must also be sincere in your repentance, treat your husband with kindness, not withhold his rights, abandon the whispers of Satan, and turn to obedience to Allah.