Before I Go to Sleep

Oh my god this book was so boring. It got a little interesting in the last 50 pages when the twist that was telegraphed in the first 10 pages of the book is finally revealed but until then I was finding every free moment to read this book so that it could finally be out of my life. This seems like a plot and format that could be really interesting and reward the reader for paying attention and noticing details, but no, it does that maybe two or three times across the entire book. Also I just couldn't suspend my disbelief with the diary entries (which make up 90% of the book) — who writes in their diary like that?????