Things like the MS-PL strike me as Open Source but not Free Software, but I can’t think of a contrary example which is Free Software but not Open Source.

My parents chose each other. They’re both good people, but they weren’t a good match at all and none of us were especially surprised when they divorced.

The Mrs and I chose each other, and while it would be arrogant to assert that we’re definitely a good match I get the impression that my kids would be shocked if we split.

The structural key to a happy marriage is, I think, the freedom to leave. If my parents had split when I was a kid they’d probably have a better relationship. But because of economics and law and pride they didn’t, which made the pain last way longer than it should have.