My mom died when I was a year old - and she was a devout Roman Catholic.
My dad was Baptist, then converted when he got married. After her death, church wasn’t that much of an issue.
My (maternal) grandparents, otoh, were very devout and gave religious instruction (and regular church visits) when we visited every summer. They meant well, so I didn’t bother rebelling, just learning how to spend up to an hour quietly thinking about something else. Law of unintended consequences: Being patient in church while somebody is droning has been a lesson I’ve grown to appreciate greatly over the years. But, anyway, I only saw them a couple of months out of the year, so it was no big thing - we just understood that when we went to see them, we’d get a dose of God. 
Anyway, the lesson didn’t really stick - one time, when they visited us in Atlanta, my father took them to the regularly scheduled 10:30am mass - only to find that the church was closed, that it had moved a couple of blocks away. My dad, caught in the act of being Exposed for Not Taking the Kids to Church, sputtered… “But this wasn’t in last weeks bulletin!” 
So it was kind of the best of both worlds - I got some religious instruction, but it wasn’t constantly oppressive (other than my wife, my grandparents are the greatest, most positive influence on my life), and I also lived most of my life with the understanding that it was pretty much a choice of whether or not you wanted to believe.
However, had my mother lived, this would’ve been a different story. She, like my grandmother, made sure that her kids were active in church. I have no idea how I would’ve handled that, so I don’t even speculate.
As for me, it’s not the idea of “God”, the creator of the universe, that I don’t believe, but the story of Christianity is pretty hard to swallow: God sent his son down here so we can feel guilty about killing him… and therefore, one will have eternal life if you accept your part of the guilt in what happened 2,000 years ago? You then have to concede that, yes, Western Civilization was rewarded for killing its God so it, eventually, gets the scientific method that allows it to conquer the globe for 500 years. I mean, last time I looked, the guy who made the decision to off God was Italian… and they get the Renaissance.
Wtf? How the hell does that work? I can see it as in those commercials…
“I’ve got an idea!”
“What?”
“If I send Jesus down to Earth… they’ll kill him. And then I’ll let them know that, ta-da!, you actually killed my boy! And if they admit that they killed Jesus, and feel guilty about it, and then believe that he’s actually my son, I’ll grant them modern civilization so they can conquer and pollute all those people who didn’t kill my only son!”
“Brilliant!”
“And get this… I’ll be very vague about it. It’s not like I want to do anything to settle the issue once and for all, like appear out of thin air to every man, woman, and child in the Universe… no, that wouldn’t work. The indirect approach is all they need to know the One True God! It will convince everybody!”
“Brilliant!”
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