I'm very much not a fan of this line of thinking. Stories are narratively contrived. It's even a maxim of storytelling: "focus on the most interesting time in the characters' lives." Stories have beginnings, middles and ends and they have nothing to do with the lives of the characters. By thinking about your own life in terms of arcs you are forcing an undue amount of importance on unimportant events. More than that, you're looking for an end and trying to redefine your beginning. Finally, by considering your own life a narrative you're forced to consider the audience who, by the way, doesn't give the first fuck about you. I'd go as far as saying that considering your life a story is unhealthy to the point of detrimental. Life is a journey. You know when and where it started, you rarely know when and where it will end. Everything else is subject to change and if you're constantly trying to arrange your existence to please some external structure you are literally wasting your life.