I don't normally buy into amnesia stories, but the twin element and the cult past made the story interesting enough for me to just go with it. The book was weird and mysterious. Those are facets I like in a novel.

Good writing and character creation but about 100 pages too long for continuous engagement and connection to story and character 

UPDATE
I feel the need to knock this down a point after realizing the full extent of the author's using a real story for the plot. I did know upfront that she was inspired by a true story of twins where one had an accident that left him with almost total amnesia other than remembering his twin's face and name. But then I learned that

the real life twins were in fact both victims of sexual abuse as children which the remembering twin tried to protect his brother from.

Knowing this made the authors treatment feel cheap and kinda gross.

Original review below.

Positives
I really tore through the first half of this book; it's really gripping in its mystery. The back and forth timeline is employed well, and Kat's journey of self (re)discovery is interesting to follow along with.

Negatives
I found the end less than satisfying -- a lot of the reveals/resolutions frankly didn't make sense.

For example:

Violet's blackmail was a primary impetus of the conflict. But supposedly the twins ran away around the same time as Jude's betrayal/Violet getting sent to the big house. But the twins get rescued by Violet's mother only days after they run away. Why wouldn't she retrieve her daughter as soon as she found out what was going on??

That was my biggest plot confusion but there were lots of little things too. And aside from Kat, I found most of the characters pretty flat.