My anecdote is to point to the rest of my parents' children along with my parents' siblings and their children. All told, you wind up with about a hundred people (big families, lots of cousins). Out of all of them, I am the only one who does not live in Texas. And, out of all of them, I am one of only five who do not live in the 30-county area known as "Northeast Texas."

It's not like my extended family members are destitute or have some external tie to where they all live (e.g. they're not all "Texas Bluebonnet Genetic Researchers" or something like that). Yet none of them could fathom living anywhere else and every year at the big family reunion, I am still (quite a few years later) peppered with earnest, wide-eyed questions about how it is to live so far from "home."

As for your experience in Colorado, my experience and that of those who I know is that it "non-natives" tend to make friends with other non-natives than with native-born people. Why? The native-born people who live where they were raised still have those social and familial connections that were made over many years. Combine that with the trend of people seeking and making fewer friend connections as they grow older and the odds grow more slim.