I searched for a long time what I believed, I knew I was not an atheist so I dedicated myself to research while I was in college and determined that deism defines what I believe.
I used to classify myself as a deist. Like you said, it was a college thing. I was super into the activities of America's founders and their belief systems. George Washington was essentially America's Cincinnatus, that's a pretty strong character. They were almost all deists.
I think most of us arrive by it honestly. You see the slight variables that allow us to exist, things doing what they do in just a certain way that allows existence. "Fine tuning" they say. But you've also read the Bible and realize that's some crazy shit.
I guess, for me, when looking at the broader scope, how much of the universe is actively hostile to us, and how much of it we couldn't go near without advanced technology, a creator just didn't make sense anymore.
Of course, I could be wrong. Maybe there is a creator out there, with his back turned. That's a conversation I'd love to have.