I suspect your son is suffering from two decision biases. One, the status quo bias, has to do with our tendency to take our current situation as our reference point and to see any change as negative (or at least difficult) and with a high potential for regret. The second, the unchangeability bias, is the idea that when we face large decisions that seem to be immutable (getting married, having kids, moving to a distant place), the permanence of these decisions makes them seem even larger and more frightening. With these two biases combined, it's only natural that your son is apprehensive about moving West....The the status quo bias and the unchangeability bias... that slots right into my own thinking about a couple major life decisions.
(The link goes to the Wall Street Journal, and here's an alternate link to the same item on Ariely's blog. It's a hassle not to be able to get useful links from the WSJ going to articles that I'm able to see as a subscriber. It makes having a subscription partly a disadvantage. I can find things I want to show you, but I can't easily tell if you'll be able to see them. A NYT subscription doesn't work like that.)