All you care about is the paycheck. I hate to be so undiplomatic, but it will always create friction in your life to have this level of religious difference. He may never want anything to do with Mormons or the church again. I don't think I'm eligible to advice, but I would say be prepared to be independent and make lots of friends. Props to people who do.
There are a great many beliefs I can't condone but most of them are along the lines of gender stereotyping, and how you apply that to your own life obviously varies by individual. Fortunately most of my immediate family has done better. But, on the other hand, maybe being a doctor is so fulfilling that they can cope better with the lack of other activities. I don't want to advocate manipulation but asking questions concerning Joseph's dishonesty about polygamy to his first wife and his marriage of other men's wives and marriage of a 14 year old may prove more fruitful than just saying wow polygamy is messed up.
The church is really good at putting on a happy, wholesome face to show the world, but if you look behind the curtain, you see that it's a despicable cult. The dots are extremely close for every LDS person, its just extremely hard to connect them. Well if she knew or ever found out, in her eyes you'll be a loathsome perverted deviant in need of sex addiction counseling. If you are both in high school, she may refuse altogether.
I'm in the exact same pulling-out-my-hair situation that you are. Yet others are really great human beings. I am so sorry for the pain you are going through.