Objectively good, subjectively not so
I stopped reading at the chapter with the second flashback. Technically there is nothing wrong with the book, I just don't like the story itself.
Read the story now
From an objective perspective, I think that things fall into place pretty well. We have the hook, the mystery, the slow unfolding of the events, the character development, and so on. The first few chapters promised a lot. The story could have gone in several directions, and it's ok where it did actually go. The writing style is great, I really liked it, and it was one of the things which kept me reading. The punctuation and the grammar were almost perfect, the sentences had a natural flow to them. This made the text very readable.
From a subjective standpoint, I didn't like the romantic inclinations of the story, there were too much of those. Also, the hints that the men might be some kind of beasts, possibly werewolves, was just too much. It's just a matter of personal taste, I don't think these are actual flaws of the story. I was just expecting something else, that's it. If the majority of people like it, then you are on the right track. I'm not on track with the latest trends, so I don't know what most of the people like or are expecting from mystery writers.
So, to summarize, you have great talent as a writer, and I think that the story has every chance in the world to become successful. It's just not for me.