I'm struggling with how to rate this one. For the first 2/3 or so of the book, it made for perfect bedtime reading: enjoyable enough for me to be eager to pick it up, but not so engrossing that I couldn't easily put it down. And then the last 1/3 or so caught me by surprise, and I was up until the wee hours finishing it.I loved Jon, absolutely adored him, even as I wanted to shake him a few times. But eventually he gets shaken and comes to his senses, and I appreciated seeing his dawning understanding and character growth. The narrative voice was so perfectly Jon, as was the whole tone of the story. That's how it always ought to be, but so rarely actually is, so I really appreciated the quality of the writing. This is a well-written, well-edited book, and that alone is a treat.I also loved Izzy, she's exactly the sort of awesome woman we see far too rarely in m/m. I was less sure how I felt about Callum. At one point John thinks, He liked Izzy but had never managed to be in love with her, while for years he had been at least half in love with Callum but frequently hadn't liked him at all, and I had to laugh because that summed it up so perfectly. It also helped me feel better about the ambivalence of my feelings about Callum. Callum also had real character growth and development, and by the end he had the self-awareness to recognize that he's not perfect, that Jon knows he's not perfect, and to appreciate that Jon loves him anyway. That is one of my favorite sort of romances (maybe why I'm not a big fan of Mary Calmes?), so in retrospect I'm wondering if the point at which I couldn't put it down was when Callum finally started to mature. I think by the end he's grown into someone who's worthy of Jon.I also enjoyed the maturation of Jon's daughter, Justine, and his relationship with her. And that even his "evil ex" turned out to maybe not be so evil after all. The characters were nuanced and realistic, with no one all good or all bad. Many of them, being actors, had a tendency to pepper their conversations with quotations from and references to the classics. Having spent some time with a theater crowd, I found that very realistic too, and it enhanced my enjoyment of the story. At times it was maybe a little too much, though I probably wouldn't have thought that if my memory of those classics was a little stronger.Having said all that, I've finally figured out how to rate this book: 5 stars. Is it perfect? No, but it's an amazingly realistic, beautiful, painful, glorious look at humans, friendship, betrayal, forgiveness, and love.Edit 30Apr2013: I decided to down-grade this to 4 stars. I wrote my review in the happy rush of having just finished the book. But I just can't, in good conscience, give 5 stars to a book that took 2/3 of its length to really engage me.