My mother converted to Mormonism when I was only 4 years old, and I was a true believer for approximately 24 years after that. This included serving a two-year LDS mission. My wife even says that when she first met me, I was "the Ambassador of Mormonism."
In February 1998, my doubts kicked in full force, and I madly tried to make up for lost time by studying everything I could about Mormonism from the viewpoint opposite the official one the Church teaches you. In other words, I began reading books which were "historically accurate" as opposed to "faith-promoting." The two concepts are mutually exclusive, I found out, and that discovery led me into the greatest crisis I've ever had to endure. Having my cherished beliefs and singular worldview torn from me was not pleasant, and now I know from personal experience that the old adage, "the truth hurts," is a correct statement. Learning the truth was well worth the turmoil I went through, however. Nothing good ever comes easy, and who can put a price tag on the truth?
Now that my perspective has changed to where I can freely take in any and all facts and weigh them on their own merits, instead of looking at them through jaundiced Mormon eyes, I'm amazed at how many things I should have caught but missed entirely simply because of the culture in which I was raised. When a person is young, he or she simply follows his or her authority figures, since he or she is not old enough to comprehend the idea of "wrongness" and that one or more of the authority figures might be "wrong." Without any contrary evidence, this unhealthy perception continues into adulthood. I excuse myself the same way: Due to a lack of contrary evidence (and where was I to look for it, assuming it existed?), I never bothered to check the reliability of my parents and other Church authorities, so I didn't catch basic inconsistencies which would have been obvious to anyone else.
Let's take, for example, the first, biggest, and most fundamental misconception promoted by the Church: Every educated, rational, intelligent, thinking person in the world bends the conclusion to fit the facts, right? If you think the world is flat, but sail off in one direction and wind up back where you started, then you bend your conclusion (the world must actually be round) to fit the facts (since I couldn't have come back here otherwise). Mormonism does the exact opposite: The facts are bent to fit the conclusion. The conclusion is that the Church is true, and all the facts are bent into the most ludicrous shapes to fit this conclusion. Post-Mormons have a phrase for it: "Mental Gymnastics." If some contrary evidence shows up which would lead one to believe that the Church isn't true, for example, all types of illogical arguments are postulated to discredit or reinterpret the evidence. When all else fails, one of a family of pat answers (secret weapons?) is whipped out: "There are some things we weren't meant to understand in this life," "God doesn't give us all the answers since he occasionally wants to test our faith," "Read your scriptures more and it will all make sense," or something like that. As for me, I could no longer do the mental gymnastics required to remain a believer. I had to start being honest with myself.
The fact that for about 24 years I didn't catch the first and most obvious inherent flaw in the system--that every educated person bends the conclusion to fit the facts, while Mormons do the exact opposite--embarrasses me now. I had fancied myself a rational, thinking person beforehand, but the fact that my nurturing caused me to completely miss such an obvious shortcoming made me cringe! I couldn't help but wonder what else I had been utterly oblivious to that everyone else takes for granted?
In spite of it all, I'm happy that there was at least one item in the "party line" which I never bought, not even for a second. The Church teaches that its members shouldn't read "anti-Mormon" literature. I didn't fall for that, since if the Church is true, it'll stay true no matter what one reads, right?
Many people, post-Mormons included, mention that Mormonism does a lot of good. This may be so, but it should be made known to the world that it also does a lot of harm, intellectually, for all the reasons I cited above. (It also does harm by placing a huge burden of time and money on its members for naught.) In my opinion, whether or not Mormonism is a good thing depends on whether the advantages (community ties and emphasis on righteous living) outweigh the disadvantages (stifling of the intellect). I suppose only time and the individual member or post-member can tell.
Where has all this led me? Today, I no longer have to be afraid of truths or facts. I no longer have the weight of a preconclusion hanging around my neck, dictating how I interpret new information. I have the freedom of knowing that all my conclusions are now fully malleable, able to change their shape to fit the facts. Learning and discovering new things is a refreshing, exciting experience, not a fearful one. I no longer recognize anyone else's supposed intellectual authority over me. Instead of having to defer, for safety's sake, to "The Brethren," since they have a direct hotline to God himself (or so I thought), I can now trust myself to be able discern between truth and error. This self-trust brings a freedom that most Mormons will never know.