We're not gonna lie. This book has a strange and not-too-joyful ending. Not to mention it basically ends twice: once when the government forces break in and shoot all the terrorists, and the second time when Gen and Roxane get married in the Epilogue. What's going down in both these endings?
In the first one, we get an abrupt and tragic ending. The terrorists and the hostages have come to understand each other as a community. It's touching. It's harmonious. It's at the height of its strange, fairy-tale beauty when it all comes crashing down.
After all, you can't live in a fairy tale forever. Everyone in the house sort of knows, when they stop to think about it, that they can't live their whole lives in the small world of the house. The real world has to intrude sometime. Which it does abruptly and tragically when the government soldiers burst into the house, killing all the terrorists and accidentally Mr. Hosokawa, too. The very last sentence of the book (pre-epilogue) tells us that Carmen and Mr. Hosokawa were accidentally shot together. Talk about your abrupt ending.
That detail weighs in with maximum emotional impact as we realize that the dream world of the house has been completely destroyed, and neither of the two romances that have been unfolding there (Gen and Carmen, Roxane and Mr. Hosokawa) will make it back to the real world. It's an appropriately stark ending for a book that explores what happens when you inhabit a dream world.
But there's a second ending in the Epilogue, where we find out that Roxane and Gen are marrying each other not long after the events in the rest of the book (though long enough that the survivors are starting to try to settle back into reality).
At first, this seems pretty odd. They were never in love with each other in the first place, and they've both lost someone they actually were in love with. Not to mention the whole surviving a traumatic hostage situation thing. We're pretty sure psychologists don't want us to try this at home.
But if we think of Bel Canto as a book with a lot of symbolism (and we mean a lot of symbolism), maybe this ending isn't as strange. In a way, the book is about the exploration of new experiences that art and communication allow. So on a symbolic level, it seems kind of appropriate that the opera singer and the translator marry each other at the end. In their own ways, they're both catalysts for the community that came to exist in the dream world of the house.
Through Roxane's singing, people unite around the beauty of music and the power of art. Through Gen, they find the means to communicate in language and become a community in that way. Language and music marry each other at the end. Which is a slightly more upbeat ending than the other one.
And also, in a way, Gen and Roxane symbolize the whole community they've loved and lost. Simon Thibault recognizes this near the very end of the book. The narrator tells us: "He [Thibault] was sure that Gen and Roxane had married for love, the love of each other and the love of all the people they remembered" (Epilogue.29).
What you make of the ending is up to you, but at least looking at it that way makes it not as much of a downer as the first one.