I would say that there are two great pillars of the Mormon faith: Truth and God.
We are taught that we have the truth because we are the restored Gospel of Jesus Christ, and we have a living prophet that receives direct revelation (truth) from God. Because we are the restored Church of Christ, we have God. The Church and God are the same in essence, and God and the truth are the same, so these two great pillars Truth and God, not only do we own them, they are basically one in the same.
As a Mormon you value the truth, and always want to be faithful to the truth. As a Mormon you value the Church, and always want to be faithful to the Church. Since they are one in the same, being faithful to both is easy and not in conflict with each other, and because they are one in the same you don't have to value one over the other... they are equal and the same. Christ is the author of truth, this is his Church, they are tied together, you cannot separate them.
This concept of the truth and the Church being one is reinforced by everything in your life. As a Mormon you may have many spiritual experiences, these reinforce for you the truthfulness of Christ's Church, that you are in the true Church and you have the truth. All of the Church's teachings reinforce this. Most Mormons have many Mormon friends and family members, who all reinforce this to each other. They all believe it and it's their walk and their talk. It has been reinforced by your family, friends, and the Church how important it is to be faithful to Christ, (which is his church) and to the truth (which is his church).
So... when you stumble upon something or learn something about the Church, that exposes it to be false, I believe in a brief millisecond you have to choose between these two great pillars, the truth and God (the church). I believe it happens so quickly that you are not even aware of the choice that you are making, or that you are even making a choice. I believe in our subconscious one of these is more weightier to us than the other, and whichever the one is, determines your path.
For me it was the truth. The truth raised up, and I saw it more clearly, and the truth set me free. For others, being faithful to Christ, (which in their eyes is the church) is most important, and anything that says the Church isn't true, or threatens the Church will be cast away immediately and quickly forgotten, while the joy of staying faithful to Christ is reinforced by everyone you associate with, and in everything you do. For the truth to dominate, you have to want to know the truth more then you want the Church to be true. It's that simple and it's that complex.
So two people, one that held to the truth and the other that held to the Church, who once held these two beliefs so strongly in common will become separated. Each one believing they are holding to the most important thing.
This is where Mormon Faith Crisis Help comes in. Until you are in this situation, you don't know that this world view you hold can be separated, and you might find yourself at odds with your spouse or family member. If you can see that the person is holding to the one that they have placed more value in, it is easier to understand where they are coming from, and to be less judgmental.