I think some weddings can be extravagant but maybe its because the brides wear white that people think it could be what it looks like in heaven with everyone wearing their best clean white clothes. Or something like that.
It's not marriage so much as the marriage supper.
But as we know, the book of Revelation doesn't specify that the bride be a woman and the groom be a man. Like its a metaphor for God marrying the land of Israel. That metaphor was throughout the Bible.
We all know marriages that go wrong, and promises made that aren't kept. Thats why it was a covenant, it could go well, but it could also not go well. It all depended on whether the Israelites obeyed God or not. Blessings if they did, curses if they didn't.
God loved other nations too, but not like He loved Israel, who was His chosen. It's nice to be chosen, but it's also a burden few people can look up to and keep carrying. It's much better to be free rather than captive. Jesus came to set the captives free didn't He?