Sylvia Day's Captivated by You

Ok, so I, like a lot of other people, picked up this series after Fifty Shades of Grey.  The first couple books really held my interest, but, by the time I made it to this one, I felt like it was really just stretching to keep the series going.  I didn't really find a purpose behind this installment of Gideon and Eva at all.  Thinking back, what was the purpose of this last book?  These people are really so dysfunctional that I cannot imagine anyone is really like this in real life and I ask myself this over and over while reading this book.  I just really felt like this installment was lucking the umph and purpose the prior three had.  Maybe the next installment will satisfy.