I stopped being a Christian about a year and a half ago, around the time I turned 19, but evolution had very little to do with it. I was raised as a Christian from birth, and accepted Jesus as my personal lord and savior when I was about seven years old. I accepted evolution gradually over two years from when I was eight to when I was about ten, and worked very hard to reconcile it with the Bible, which I did for nine years.
One of the ways that this eventually turned me away from Christianity is that it was one of several examples of Christians in general being no kinder, more logical, or more knowledgeable than any other group of people. Even if the Bible CAN be reconciled with evolution, God appeared to have made this reconciliation so difficult that most people either reject the Bible as I did, or use the notion that it's divinely inspired as a basis to conclude something false. If he wanted the Bible to serve as a guidebook to future generations, why did he make all of its descriptions of the physical world so unclear that people would conclude something incorrect from it until the physical evidence disproved them?
Evolution is the most recent example of this, but it is not the only example. People have also used information in the Bible to conclude that the world is flat, that animals cannot become extinct, and that the sun and all the stars and planets revolve around the earth. In each of these situations, the belief persisted until physical evidence forced Christians to re-interpret the Bible.
This is actually part of a much larger question of why God makes it so difficult for us to do what he says he wants us to do. I've explained in another thread that for God to have created all of space at once, he would have had to create all of time at once also, since neither of these can exist without the other:
http://www.christianforums.com/t85666&page=1 This means that God chose for evil to enter the world, and he also chose to make Adam and Eve in such a way that they would be susceptable to it. The argument that making the universe differently would have given us less free will falls apart once one realizes that God has already planned every choice that humans make--after all, that's part of time also--and if he had made the universe a little bit differently, the only difference would be that the things we choose would have been slightly different.
To put it simply, all of my evidence in favor of Christianity has disappeared. All of the aspects of the world that it explains can be also explained in other ways. (I could give some examples of this, but it could probably be an entire separate thread.) There are also no predictions that the Bible makes that I could use to verify it, and all of the things that it appears to predict about Christians' behavior and their lives don't appear to exist either. (I'll also give some examples of this if asked for them.)
When I've discussed these facts with other Christians, what they eventually say is usually something like that the whole point of faith is that you believe something even when there's no evidence for it. That may be, but if there's no evidence to support Christianity, then there is nothing to recommend it over any other religion. I will always believe what I think is most likely to be true, and if the most likely thing isn't Christianity, then I think I should believe something else.