Thanks for your insights (and sympathy).
The fact that L's job is so far away from home IS undoubtedly a big problem - but it's a very hard one to solve.
Our town's biggest employer closed last year and took 30% of the town's jobs with it, not to mention all the people who lost jobs and businesses in the fallout from that closure. Our town already had 25% unemployment before the closure, and the property market is now down the tubes, so we almost certainly couldn't sell our house even if we wanted to.
So, realistically, for the short term at least, I'm stuck here and he's stuck there.