About your brother and his girlfriend. You said: "With so many people getting divorced, why not live together to make sure it's right."

Logical, except living together and being married have nothing in common!

Marriage is commitment; living together is noncommitment. Relationships can't be done on a trial basis. They're too hard.

Without the bonds of commitment, it's too convenient to bolt. People who live together are always asking "is she gonna bolt on me?" or "should I bolt on her?"