Image by asparagus_hunter via FlickrMy ex-relationship with Christianity is perhaps unique, in that my family attended an Evangelical church, but one whose pastor was nonetheless pretty progressive or diplomatic in his views. (i.e. he rarely mentioned hell, End Times, or even sin in his sermons. It was just "love" and "the Good News.")
But the Sunday School classes (6th grade specifically) were taught by less diplomatic people. They were volunteers which basically meant two things: they obviously were passionate about what they were doing to do it for free, and they had no worries about money or church attendance, so they didn't need to be uplifting or popular in what they said.
So as my parents listened in the main church building about how God is love and sin is forgiven and nicety after sugar-coated nicety (as, I've come to learn since, this is pretty much their entire view of Christianity... they are not fundamentalists, thank goodness) I was in another building in Sunday School, listening to fundamentalist lunatic volunteer "teachers" spouting off about the End Times, God's wrath, Hell, and forcing us to sit through the Left Behind movies. I'm 19 now, and this was right after 9/11, so we also got tons of sermons about how 9/11 was a sign of the End Times and that it proves what worshiping "false" gods leads to.
So for many years I internalized this (I was only 11 after all) believing all of it was true. I lay awake at night worrying that if I drifted off to sleep, my family would be raptured overnight and I'd wake up alone in the "Great Tribulation." (My ironic belief being that if I were awake when the "Rapture" occurred, I'd at least be able to argue with Jesus that I was a "real" Christian and perhaps convince him to take me along after all)
After 6th grade, junior high and high school @ church were fine because, once again, they catered to the students' desires to fit in, find "family," be accepted, etc. So it was very candy-coated, love-centered, and progressive (or as progressive as a Baptist church can get).
I believed in a very vague Christianity throughout high school as a result, never questioning it and at the same time rarely thinking about it or letting it affect anything in my life. I went to church without complaint and didn't mind because I never listened anyway, and I liked to go out to eat afterward.
After reading Sam Harris's Letter to a Christian Nation, I am now fully an atheist. Luckily my family has been pretty supportive though they are still Christian and don't know I'm an atheist, just that I am no longer Christian. For a brief period I had a Muslim girlfriend (the relationship soured because... YOU GOT IT! I wouldn't convert to Islam) but my family accepted her and did not tell me they had a problem with the fact she was Muslim. My mother even told me, "She's a keeper." And this had a severe effect on me. On one hand, my mother believed that this woman would spend eternity in agonizing fiery torture (simply for not believing in something) and on the other hand she liked her and said that she'd be a good wife for me, even. This really showed me the divided-ness of a religious mind. The reason they can go on believing in a God of "love" is because unless confronted with questions about Hell, etc. They don't think about it much. They focus on the good feeling they have at church or while praying, and the "message of hope" and almost entirely ignore the sinister parts of their faith.