Her Religion is the single most important thing in her life. And here's an excellent video on the importance of religious freedom. Today, at my ward sacrament meeting, in the back section of the chapel where I was sitting, all the women except one were Mormon wives in interfaith families. Interreligious marriages are not a new thing.
I am a non Mormon. Stopped answering texts and calls, refused to give me my belongings that he moved up to the new place, and not to mention he broke up with me over the phone after all of those years. The Mormon culture has mastered the forked tongue. On her mind, her eternal salvation depends on marrying a worthy priesthood holder. He took out his bad moods on everyone. I only hate one thing in the planet, and that's the Mormon church. But she understands that I am committed to the Gospel, and will never leave it either. I feel selfish to never be around but this is my dream so much so that I refuse to have children because I dont want my kids to have a workaholic mother who's never there.
When out on a date with a Mormon guy or girl, be very decent, courteous, and well-mannered. I have been dating a surgeon and we are thinking about marriage. Make sure she knows the plan, so you both can dress appropriately. Put your best foot forward; be soft-spoken, courteous, well-mannered, chivalrous, and respectful.
Trust yourself, trust God and enjoy the beautiful relationship that you have. If you are both in high school, she may refuse altogether. The way he wanted to live his life, the family he wanted to have, the wife he dreamt of- matched the type of person I longed for. And I don't have issues with her, hell, haven't even seen her in over 20 years, but the experience with the whole Mormon thing gave me better insight in to many things in life.