Where or When - Anita Shreve

What is it about love that can't be controlled? Is it just the hormones, or emotions running deep? If love matters so much, then is love right even when it stands to break existing families, separating children? What is important?
This book reminded me slightly of Kabhi Alvida Na Kehna, where you stand to question the idea of fidelity. They say, if you are not happy with somebody, then there is no point continuing in a loveless marriage. And if you find true love elsewhere, even if both parties are married, what about then? This book left me with unending questions...