When I was ten, my father and brother drowned in a boating accident. My brother was 17 and a month from going to the University of Illinois on a full academic scholarship. It was a beautiful day and I remember thinking it should be raining; wondering how it could be nice outside when something so devastating happened. For years afterward, I marked time as before and after "The Accident". That's a personal example of a life-altering event, but I'm sure you can add many more. In fact I'd love to hear from you about them.
In "Halifax" http://bit.ly/JoanMauch Ellie's life-altering event came at the barrel of a gun. For her, everything from that point forward changed - her outlook, her relationships, everything. Our lives often are defined by the divide between what was then and what is now. The trick is to treasure our memories and learn to live - even love our unexpected new reality .