Step one: It's recommended that one should quit the Mormon church, it's filled with creepy, greedy, and fucked-up practices on top of it being a church that's started by a bat-shit crazy scam artist (much like scientiology, only back in the 1800's and it being christian based). Fuck, even Catholicism seems appealing in comparison to those dumb fucks. Step two: Learn grammar, because we gotta be able understand what the hell you've just typed down. Step three: Learn to explore the world, explore yourself, and overall, live a worthwhile life until you've found someone along the way. Chances are you'll find someone that isn't a Mormon that won't treat you like that.
TL;DR, forget about him and go have fun with your life.
My ex boyfriend is mormon. He broke up with a few months before leaving for his mission because he didn't want to be 'pulled in', whatever the hell that means. Anyways, I've only written to him once since. I figured that things would play out when he got back about the same way they did with you. Missions change people.
Maybe it has something to do with his religion. Back when I used to go to church, I knew several couples, who loved each other, but were told by the pastor that they can't get married because "gawd said so" and one of the parties ended up marrying someone completely different very shortly after breaking up to a person the pastor thought to be more suitable. When I grew up and left, I realized the pastor was just trying to marry rich people into his family and church in order to get his hands on all of that glorious cash.
I know. When I first started suspecting shit, I didn't want to believe it, because my whole world started crumbling, but as I grew older, I realized just how full of shit the church leaders actually were. On another fucked up story from same place: the pastor's eldest son divorced his wife after less than a year of marriage, because he wanted her to pop out babies and she wanted to study in uni, because that particular thing she wanted to study and make a career of was her dream. She was boo'ed by the son and pastor as an "unfit" woman, because she "disobeyed" her husband.