I was a christian most of my life, but there were several reasons i could no longer reconcile the basic christian theology.
The momentum started when i chose to thoroughly investigate the NT, by reading the works of various well credentialed NT scholars and historians. I learned quite a bit through that process, which causes me to take a step back and really analyze my belief. As i did and i overlay the basic christian theology, with the evidence we have about the world and universe we live in, it just did not align with any level of logic to me. The traits christianity places on god, dont relate to the world we live in. Also, the whole piece of christianity (most christians at least) that one must be a christian or they are basically doomed, appears morally corrupt to me and quite primitive. Tends to smell like a man made religion, that wants to scare people to stay in line. If you look at the world, ones religion is mostly formed by where one was born and who their parents where, which is another indicator different cultures search for answers and form their own religion. According to many who are christians, 2/3 of the worlds population is doomed. Not quite the loving god who cares for all his creation equally.