For most of human history, religious identity was not chosen but given — the faith of the community into which one was born, absorbed before the self had the capacity to evaluate it. The believer, the doubter, and the leaver are not three different people but often three phases of one life, and the transition between them is among the most identity-intensive experiences a person can undergo. Juana was a nun who doubted and inquired without quite leaving — which may be the most honest position of all.
Each step builds on the last.