I am sorry you are struggling.
For many people religious beliefs are a big foundation for a relationship and marriage, especially if they want to raise children. It’s not uncommon for people to date and marry within their faith. In addition being excommunicated from one’s religious institution means a lot to some people. It’s not something they take lightly.
Of course you have rights to express your feelings on the matter but she also has rights to not date outside of her faith.
I am not sure why it’s crucial for you that she knows she’s not an honorable person? How do you define what’s honorable? You don’t think people have rights to have preferences in a dating partner? Everyone has them. For her it’s having the same faith. For others it’s something else. It’s hard but that’s how it goes. Not every relationship is going to work out