Help: It’s Been Driving Her Nuts for Years

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Bitchery Reader Amanda asks for your brilliant assistance:

I never actually read this book, but I read the excerpt in the back of
another romance and thought “that sounds fun in a melodramatic family
soap opera sort of way” and told myself I’d pick it up on my next trip
to the bookstore. Except I forgot. And by the time I remembered the
book the excerpt had been in had been weeded out of my romance collection.

So here’s what I remember: contemporary, takes place in the Pacific
Northwest (part of me would swear to Oregon, but its highly possible
it’s either Washington or Northern California too). Girl was in love
with her older sister’s boyfriend for years, older sister went off to
conquer the world, boyfriend and younger sister have a Night of Passion
that results in pregnancy. They get married. Now, ten years later,
they’re getting divorced/have been recently divorced despite the fact
that she’s still desperately in love with him. To top it off, her older
sister’s coming home for the first time in years!

Our heroine was named Allison and I think her sister was Terra or
Tessa. I also distinctly remember the hero being quietly angry in the
first chapter because Allison showed up early to pick up their daughter.

I think it might be a Barbara Delinsky, but again, I wouldn’t swear to it.

Ring a bell anyone? Anyone? Beuller?