Why is a Catholic girl married to a Muslim not allowed to celebrate her religious holidays, and can she worship according to her beliefs while remaining true to her faith?

The Christian woman who wishes to marry a Muslim man must understand several matters: obedience to the husband in matters that are not sinful, the husband's right to prevent her from going out even to church, and from displaying forbidden things in the home such as Bid'ah (innovated) holidays, and preventing her from drinking alcohol and eating pork, while not compelling her to convert to Islam or preventing her from her private worship such as prayer and fasting.