Cardiff, by the Sea: Four Novellas of Suspense

I generally like much of the literature Joyce Carol Oates puts out. I have enjoyed most of her novels, her horror, and her slice-of-life short stories. This book has 4 novellas. The first is a very long story with an interesting plot. An adopted girl who has not idea of her biological past gets a letter that sets in motion her being confronted with very startling information about where and who she came from. Unfortunately, the story just ends. Just ends. The big question that lingers over everything is not resolved at all. I went back to re-read the last 40 pages to see if I missed something; but it appears that Ms. Oates is going to leave it up to the reader to decide which scenario is the truth (but leaves us without enough information to make that leap). Hated, hated, hated the ending. Felt like a waste of 150 pages of what could have been a really great story. I didn't even bother reading the rest. She really bombed with this book.