The critics would have you believe that they are disinterested pursuers of the truth. There they were, minding their own business, going about their conscientious study of church history and—shock and dismay!—they came across this (whatever this is) that blew them away. As hurtful as it is for them, they can no longer believe in the church and, out of love for you, they now want to help you see the light of day.
Let's get one thing clear. There is nothing in church history that leads inevitably to the conclusion that the church is false. There is nothing that requires the conclusion that Joseph Smith was a fraud. How can I say this with such confidence? For the simple reason that the Latter-day Saint historians who know the most about our church history have been and are faithful, committed members of the church. More precisely, there are faithful Latter-day Saint historians who know as much about this subject as any anti-Mormon or anyone who writes on the subject from an outside perspective. In fact, with few exceptions, they know much, much more. They have not been blown away. They have not gnashed their teeth and abandoned their faith. To repeat, they have found nothing that forces the extreme conclusion our enemies like to promote.
If those who know the most about Church, or Mormon, history have not abandoned their faith upon discovering all the (supposedly) shocking things found therein, then I think that should give us nonspecialists pause before we abandon ship at the slightest adverse wind.
(Or, if you need a shorter read, check out the last three paragraphs in this post by Daniel C. Peterson.)