The book doesn't get off to the best start, describing how Holly and Jack meet on a bus. It's quite slow moving and you do need some patience as initially it feels like wading through treacle. However I would urge that you give it a chance as, despite being a slow burner, it really is a great read and it does become unputdownable. Tainted evokes a mixture of emotions in the reader, from sadness and grief, hope, disbelief and at times it chills you to the core.
The characters are not all likeable, but they are not meant to be, and I think the fact that the reader becomes so angry at Holly's naivety just highlights what a good job the author has done with the characters. Also, it's interesting to see Holly come out of her shell as the book progresses - going from an innocent girl to Jack's wife. Jack himself is portrayed very successfully as a complex character and there is much to think about even after you've finished the book. It is not cut and dried and the ending leaves you wanting more.
I haven't given it a full 5 stars as I didn't really like the constant use of italics and also I thought that the book jumped around randomly at times - there would be lots of chapters in the third person and all of a sudden it would be in the first person, either Jack or Katy. That didn't work for me. Nonetheless, I did really enjoy this book and I would definitely read another book by Brooke Morgan.