I've moved to be with him for med school, then we moved again for residency and just moved again for fellowship. It's not that she doesn't believe you right now, but it is a bone she will never drop. I'm glad you both have found a way to get past the incredible forces that are working against you. About ten years ago, I realized I needed to quit qualifying my excellent husband who is a better man than many Mormon men I knowI realized I needed to raise my kids to think of him as completely equal to the men they knew at church. Alot of TBM women won't even consider dating non members. I have been dating a great guy for about a year now, and we started dating shortly after my parents died of cancer. The decisions we have made in how to raise our kids have been our decisions alone. We should all remember this is a human being, and she has a brain. He says it is harmless and is only fantasy as there is no touching involved. Break it off amicably now, before it gets too difficult.
If you can genuinely deconvert her then cool. Nothing less will do. She will want her kids blessed, baptized, taking temple trips to baptize for the dead, hold the priesthood, a bishop will ask you sons and daughters if they masterbate and punish them if they do, etc.
I decided that if the church taught the general principle that couples should be married in the temple and that was not possible for me if I married this girlthen I should see if my choice would be an exception to the rule. Husband has affair with me, after telling me that he and his wife have grown apart, and we were together for five years. Honestly, it isn't her fault. However, for me, there have been some perks too. I don't see anywhere in your post where there is a complete commitment. Mormonism has a lay clergy, so everyone serves in the Church. I recently left my family, friends and state to move across the country to be with my best friend and boyfriend during his residency. That is the shit storm on the road ahead of you. We lived about miles apart for the first 2 years.
I would advise you to try to be as understanding as you can of her point of view, because having you world view shattered is very difficult and can take a long time to recover from. Am I dating a douchebag. Learned by me in time and tears. Then again, I doubt any man who's not in medicine is willing to put up with the sacrifices of being a neurosurgeons husband. Part of me feels like will I ever get chosen for one weekend as a priority over medicine. You can't force her to change, nor should you if you could.