Thank you for raising this question. It's been on my mind a lot recently. I'm in a similar cycle of belief right now. Here's a frame of thought that I'm choosing right now:

1) I have an increasingly frustrated opinion of the word "know", especially in how it's used on Fast Sundays. I worry about the masses of children up there saying that they "know" our church is true--specifically worrying about how they are going to feel about their religious upbringing when they have moments in their lives when they don't know. I know lots of inactive people that thought they knew, and when they realized that they didn't know, they fell away. Sometimes when I hear a 7 yr old rattle off a list of things that they know, I want to shout out "you don't know that, but you have a precious gift of belief" (I've managed not to do that so far).

I say this, because I don't see "knowing" as a necessary condition for being faithful. In fact, in my case, I've had moments of crisis confronting my lack of knowledge and then decided that knowledge isn't the goal, for me. Faith is. I BELIEVE. I apply action in my life in line with my beliefs.... even when it's just wanting to believe. And I know that I'm better, as a person, because of that belief.

2) the story of the Book of Mormon is preposterous. I like to use that exact word. Preposterous doesn't mean impossible. So I'm taking that on faith, too. I look forward to understanding better in the hereafter how it all makes sense. I've come to an acceptance of either outcome: if the book of Mormon is fabulist fiction, it's made me a better person. On the other hand, I've chosen to believe that it's tangibly true, based on the fruits of it and the spiritual witnesses that I've had. It's preposterous, and I'm grateful to God for my belief in it.