I'm a widowed mother of four kids. I grew up an agnostic (the product of an armed truce between a lifelong Episcopalian and an atheist), but when I got married, I decided to adopt my husband's faith and become a Lutheran. Ours was the liberal sort of faith, the sort that doesn't accept the Bible as inerrant, that mostly ignores the Old Testament, and that handwaves over most touchy theological questions (such as the problem of evil) by saying, "Oh, God knows better than we do."
But a few years after my husband passed away, even liberal faith became too hard for me to believe. My oldest child (who has a strong tendency toward freethinking) set off my crisis of faith by pressing me on what I believed and didn't believe. I struggled, but couldn't manage to come up with a coherent explanation for why I believed some parts of the Bible, and not others. The hardest thing to explain was why I believed that in the long run, God would save everyone, and that no one would go to hell. I quoted the Bible: "For God so loved the world..." and said that if God loved the world enough to give up his only child, then surely he loved us enough to save everyone. She countered by pointing out that Jesus himself had said that nonbelievers would go to hell, and didn't I believe in what Jesus himself said?
That was the beginning of it. From there I started reading the usual books on "the new atheism," and rapidly realized that I no longer believed. The hardest part was giving up my belief in the afterlife-- I really wanted to believe I'd see my husband again, one day. But eventually I realized that what I wanted wasn't the issue; what mattered was what was. And so I fully turned away from my religious beliefs.
The problem was, however, that I had married into a family of stalwart Lutherans. In order to keep the peace, I didn't particularly want to go public with my atheism-- it might set off a very ugly familial war. Also, my children, particularly the older two, were brought up going to church every week, and they prefer to remain a churchgoing family (even despite the oldest's freethinking ways). They like the community of church, even if they're somewhat cynical about the actual meaning of worship.
In any event, I don't want to brainwash my children with my beliefs one way or the other. So I continue to go to church (reluctantly), even to the point of hypocritically taking communion-- which to me is merely bread and wine, anyway. But I also try to clearly convey my cynicism about religion to my children. It's an awkward, messy compromise, and I don't think it will work forever. But right now, it's the line I'm trying to stay balanced on.