Q1. Is it OK for a Mormon and a Christian to date?
Q2. If a person is an atheist and dating a Mormon, will the Mormon faith accept the individual?
Interfaith dating is not prohibited but there is a slight caveat that goes with this. Generally, interfaith relationships are discouraged by many religious groups based on the inherent differences in such fundamental beliefs. That is, on top of personality differences, other differences in cultural and religious upbringing just add potential problems that must be dealt with. Something that is so basic to a person’s being, such as religious belief, can cause great problems down the road.
Dating can also be difficult when the standards between the two parties differ. Young Latter-day Saints are encouraged to date only those with similar standards and goals. That means those who keep the Word of Wisdom, the Law of Chastity, attend church and have a goal to be married in the temple. Since these are generally peculiar to Mormons, it can be hard for two young people to reconcile these differences. Pressure to change from one side to the other often occurs and, if left unchecked, will eventually destroy the relationship. Members of the LDS Church will do what is normal for him or her. No drinking, no smoking, keeping the Sabbath Day Holy, no pre-marital sexual relations, and others. A person who chooses to date someone who does not follow even one of these standards runs the risk of compromising his or her values, possibly creating a division in the relationship where the desires of both sides cannot be met.
While this division may or may not be crucial during dating, any division can be fatal to a relationship after a couple gets married. Since dating is a precursor to marriage, the question of inter-faith dating applies even more strongly to marriage. In my opinion, ideal marriages are built upon common trust and unity and a marriage that isn’t progressing towards those ideals is likely not progressing at all, which is a bad situation. A good, strong marriage is one where a man and a woman agree to put aside differences and work together. Religious differences can be difficult to put aside.
For the second question, the answer is yes. The “Mormon faith” accepts any individual (see 3 Nephi 18). That being said, don’t be surprised if you are encouraged to attend church and learn more about it. Mormons are Mormons because they enjoy what they believe and derive much happiness from it. And when any individual has something that makes them happy, they want to share it with others. I also encourage you to learn more about our faith if for no other reason than to understand what your significant other believes in.
An article was published in the church magazine, The New Era and answers the question from the point of view of the LDS member who asks if it is ok to date non-members.
I will never forget the day that the Holy Ghost witnessed to me that Joseph Smith truly did see Heavenly Father and Jesus Christ and that through him the fulness of the Gospel of Jesus Christ has been restored. It had been a rough few days. At the time I was spending 8-10 hours a day learning a language that was so foreign to me (Russian) and I was suffering from immense feelings of inadequacy. I was faced with the realization that I had left everything that was familiar to me for two entire years; I felt isolated and completely alone. I realized for the first time that I wasn’t as tough or as smart as I thought I was, I felt that I was a little child again. In addition to learning Russian, I was also learning how to teach. Part of this learning process included teaching various principles of the Gospel. Of course, I didn’t know what I was teaching verbatim, so I was reading and teaching it to my colleagues. I came to Joseph Smith’s account of what he saw on that spring day of 1820 in a grove of trees near Palmyra, New York:
As I spoke these words, it was like there was a fire in my body, even to the point that I wondered if it could consume me. My heart was burning so strongly and I was so overcome with a feeling of peace that tears flowed freely from my young eyes. I knew that it was the Holy Ghost bearing witness to me that what I was teaching was true. It was so powerful that there was no room for doubt in my mind any longer and I knew that it was from God. The language still wasn’t easy and it was still hard learning to adapt to my new situation, but I pressed forward with a sure conviction that The Church of Jesus Christ of Latter-Day Saints is Jesus Christ’s church. (As an aside, I hope that you can now understand why Mormons believe so strongly in their religion. One cannot deny that an experience such as the one that I had is from God.)

Members are reminded that finances, schooling and other worldly concerns are not God’s concerns. Sometimes faith is required when the world would say, “That doesn’t seem wise, considering your circumstances.” I have known couples who have waited to begin their families until their positions become more secure and I have known couples who have started their families despite many secular obstacles. It is not the position of any outsider to make a judgment on such a private, individual matter. What is right for one couple may not be right for another.