Why People Walk Away From Their Faith
1) The study of science & philosophyAs I said in my book I was hit by so much at once that I cannot say which of the six was a dominant reason for me leaving the fold. They all hit me at the same time.
2) The sense of absence of any caring God
3) The critical examination of the scriptures.
4) Disappointment in God
5) The hypocrisy of Christians
6) The perception of a dogmatic anti-feminist and anti-homosexual stance of fundamentalist Christianity.
Link.
Like Ken I would be interested to hear from others as to why you abandoned your faith.