Much has already been said by other viewers about the relationship of the characters in the movie. Viewers have rightly noted that the characters live in a world of chaos when everything seems to be falling apart: the everyday comfortable world, the family ties, the rules and inhibitions. But such circumstances bring out in people what they really are. People set aside social convention and struggle for survival, need of love, protection, in a desperate search for something to hold on to in this world. They build a small fragile world of their own, which may seem pretty strange, but the only one working at the moment. They form the most sincere primeval bonds, and these bonds shatter one day when the outer world reminds the isolated group of survivors (noble savages) of itself. Yvan gets caught, and the truth about his past becomes known, and it suddenly matters. Odile and the children betray Yvan, failing to claim him as one of their own, flinching from his identity and background. I think that that is the ultimate reason for Yvan's suicide: he can't stand this abrupt end to the only spell of happy life he must have known, he can't survive this betrayal. And the betrayal backfires on Odile and the children: their life in the refugee camp also debases them, the outer filth of the camp and thelack of freedom they used to enjoy in that forgotten country house is the price they pay for their cowardice and indecision at the most crucial moment. One white lie, making it possible for Yvan to gain time, to escape, and everything could have been different. I think they slowly start to learn their lesson, but the price paid for this lesson is too high, and the bitterest thing is that it's not they who pay it.
