Character Analysis
Simon is the French ambassador to the host country. Edith is his elegant wife. They've been married for 25 years. They didn't want to go to the host country in the first place: they were hoping for an assignment they'd been promised somewhere else (1.17).
But the assignment they didn't want had the wonderful side effect of letting them fall in love all over again (1.18-25). Not bad, huh?
But what is bad is that the hostage crisis separates them from each other. Okay, metaphorically it draws them even closer. But in the non-metaphorical world of cold hard facts, it means Edith is set free with most of the women and Simon is stuck in the house for the whole darn hostage crisis (2.177-179).
Still, that's sort of good for us, the readers. Not because we don't want them to be happy, but because it does something interesting in the book. It gives us one character who desperately wants to get back to the real world, because he loves someone there. That reminds us of what's good in the world outside the house, even as the others are becoming absorbed by the utopia within.
It seems highly appropriate, then, that Edith and Simon are there at the end of the book to celebrate the wedding of Gen and Roxane. They can bridge the world inside the house to the world beyond it.