This. I grew up experiencing just about every flavor of protestant Christianity you can imagine. I wasn't a rebel and I was a great student of the Bible and of faith in general. I had really bought into it at certain points, but later on when life forced me away from the 'fold', I realized what a self-licking ice cream cone it was. It dawned on me just how preposterous all the variations in beliefs and self-serving interpretations of scripture were to reason. Even though I knew how silly it all was, I felt guilty and ashamed for discarding all of the effort and training that I had been forced into as a younger person. Bottom line is that you can either accept the physical world for what it is proven to be, or you can play make-believe for purposes that make you sleep better at night or give you peace in the thought that you're part of something bigger plan for the universe
It was said earlier that religion makes some people live better, happier lives, and that's cool. But it also has destroyed so many relationships, lives, and even empires over the course of history that it truly is a plague on humanity.
What made it really easy for me to break away was the realization that religion is kind of like magic - people buy into it because the showmanship and theater (and fear) means that it looks great when you're in the crowd participating and being told by everyone else in the room that "this is the truth". Interestingly enough, that's exactly what cults do as well. The only difference is that a cult always haa some dude at the top that knows the whole thing's a sham. In a religion, that dude is dead.