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Can you live your whole life with a husband you doesnt or never will believe in the mormon church.
If she is motivated enough to want to go on a mission, she will likely not settle for having a second class "eternal companion" you who is a convert or one who cannot be sealed to her for eternity.
The Mormon youth must not date before Aside from that, the Church also discourages them from getting into a serious relationship before they consider getting married. If you are only after non-serious dates and spend a great time, you should be fine with this set up.
We'll have to discuss that, now that I actually know some things about some things. I hate to say it, but if you are serious, go explore her world.