Which of the four crises/turning points do you think left the most lasting imprint on the author?

By my count, four crises or turning points marked Kanigel’s life during these five years – his growing abhorrence for his work at the Ammo lab; his split from Bev; his relationship with Maura; and his transformation into a writer. Which do you think left the most lasting imprint on him? Why?

I think the first two on the list stand by themselves, but would Kanigel have turned into a writer without his relationship with Maura? I felt that the two are deeply intertwined, and together are the actual turning point in his life. I am guessing that Kanigel feels the same, because of the depth and feeling with which writes of this relationship decades later. The relationship with Bev seemed flat in comparison.