I don't believe in the Bible either. I struggled with the idea of God for many years after leaving the WT. It was a full two years after I left the bOrg before I ever considered that the only reason I didn't look into evolution or the idea that God might not exist was because I had been programmed to think these ideas were not worthy of entertaining.
It took another two years of a lot of research and personal thought to feel comfortable calling myself an atheist. I didn't choose to be an atheist I simply found myself there after a lot of research into the bible and various other religions.