I was raised Catholic but lost the belief quite young. Not to be an edgy atheist, but it was basically lost along with Santa. I probably spent a decade trying to believe, but to no avail. I think having a chronic pain condition from a young age probably makes it difficult to believe in any sort of loving force in the world, and then a few observations about the way people who say they follow these religions actually behave will often further disabuse one of that notion.