I didn't, but at the same time I did. I was raised Fundamental Baptist, however my first baptism was Roman Catholic as an infant. Never had any RC exposure, though. Was raised Fundamental Baptist. I left, well, because it was Fundamental Baptist. Not much more to say. I went to the Christian school, though, and I saw lots of hypocrisy. My pastor would preach sermons about how we shouldn't be going to movies, even if they're wholesome movies, because someone could see you in a movie theater and it'd ruin your Christian testimony. That and he'd have like month long sermon series on the supremacy of the KJV. But the worst things were in the school. I'd get in trouble for not having a haircut, because my hair would be like past my ears, and that wasn't Christian apparently. I was in no control over my haircuts, my parents were, but I was being punished. I'd also get in trouble for things like forgetting to wear my belt with my pants. Now I can look back and see that the reason I was so disorganized as a kid and kept losing my belts was because of my NVLD, but yeah. They'd make me wear a rainbow rope if I forgot my belt. So at 6-7th grade, I left.
Then for until what would be 11th grade in high school, I was still "Christian" but was functionality agnostic. I'd gone to my friend's Lutheran church a few times and liked it, but we could never work out the logistics of getting me to go with him, so no church.
Basically, after a bunch of bad stuff happened in my life, I decided it was time to turn back to God. So I went with my friend to a church that actually started out of my old high school's Christian Club. I really liked that a lot, and grew as a Christian. The church was a Charismatic Protestant Church. Basically as far away as possible from Fundamental Baptist. You'd sit at coffee tables instead of pews usually. Lots of home Bible studies and stuff. It was really really fun, actually. You got lots of friends instantly. Unfortunately, that was the place I found out about the reality of my Aspergers, due to all the socializing. It was the first time in my life I ever had a large group of friends, a "place to belong" if you will. I ended up leaving due to a lot of reasons, some theological, actually a big reason was a girl I liked a lot there (maybe love would be the right word, but who knows) who got married, and I never told her how I felt. Another big thing was burnout. Due to my social difficulties, I couldn't bring in other people to church. I didn't really have any friends my age besides the ones at church. In a lot of ways, looking back, lots of things about the church were cult-like in the way it was ran, and the emphasis on getting lots of members. In the end, I just couldn't hack it. I failed.
So, figuring "hey I still better go to church" I did lots of boring theological reading online, and finally read about Eastern Orthodox Christianity. Because I felt like I failed God, I had a lot of arguments in my head about the providence of God, why would God create me to fail due to my AS? With Orthodoxy, though, there were monks that were literally hermits who just prayed a lot. In a lot of ways, the church is just easier socially. It's hard in other ways, things like fasting and prayer, it holds you to very high standards to. Except unlike in Charismatic churches, nobody really yells at you, you're counseled individually by the priest and that's it. But the measure is quite high. I think some draw, too, was culturally it's far away from Protestantism as can be, but it's still Christian. I looked into Roman Catholicism, too, and was interested at first, then I got invited to a Catholic prayer thing, and the guy was preaching weird like Hindu-style meditation and stuff, so I just left. I knew things were not right in Rome. Then I went to the Orthodox church and like, felt at peace if you will.
So, I didn't really leave my old religion, I'm still Christian, just it was a long bumpy road. I'm no longer Fundamentalist Baptist, though.