What happens when you can no longer do what you're supposed to do?

In Nick Hornby's latest book, A Long Way Down, four characters meet on a rooftop that is famous for jumpers. Each character has hit their respective lows to bring them to this point. Jess, an American, has arguably the 'lightest' reason: his band and his relationship with his girlfriend dissolved. Compared to a television personality who just got out of prison for sleeping with a minor and a middle-aged woman who is tied to her disabled son, Jess' trials are pretty light stuff. But the volitile teen, JJ, sums up his situation perfectly: "You thought you were going to be someone, but now it's obvious you're nobodyy. You haven't got as much talent as you thought you had and there was no plan B, and you got no skills and no education, and now you're looking at 40 or 50 years of nothing." Ouch - But her perceptions cut through all the BS. And it makes me think of what happens when people reach that point. Let's be honest - for every successful writer or musician, there's a struggling writer or musician who reaches a point when the well dries up. They're not supposed to be a writer, so they enter the world of insurance. The musician takes a job at an oil rig to pay the bills and that job turns into a lifelong occupation. This doesn't have to be a tragic end. Just another stage in one's life, right? But I was just curious - what do people do, when they reach that cold realization that what they thought they were supposed to do with their life ends ... And don't say 'pick themselves back up' - because that's too easy.