I think Beth fell in love prematurely. She admitted to herself in falling in love with Ian at the time when she doesn't understand his peculiarity yet. I don't think anyone could fall in love with somebody said to be crazy. The normal first reaction would be avoidance and maybe some pity (not sleep with the person) then love will develop after having spent enough time with the person and ascertaining that he/she is not really crazy. I like how the story was written though and how the mystery slowly unfolded as the story progressed. Some things were also left masked enough for the other characters who will appear again in the succeeding books in the series to remain intriguing.
I chose to read this just to complete a series reading challenge and lucky for me, I really liked it. I will surely read all the rest with much enthusiasm.