Book name, young adult?

I read this book about 10 years ago. The basic premise, of what I remember, is about a young woman (or teen) feeling her home in India. She comes to the US and nannies for a well off family in San Francisco or similar. Then she ends up marrying a paralyzed war vet. They adopt a teen boy and she also gets pregnant by her husband. In the end she leaves him to run off with the man she nannied for.