Did she really have...(spoilers)

Yes, she had a child with her second husband. That's why they talk by skype, so that the audience can see she's 'real'. Notice how when she reads and imagines in her mind the devastating moment in the book when her 1st husband finds the murdered bodies of his beloved wife and daughters, how she quickly calls her own 'real' daughter to check up on her?

In the end, her book makes her recall what a good man she left and what a terrible thing she did aborting his baby in order to start a new life with her new soon to be wealthy and ambitious husband. Her daughter is doing her life, her husband is away most of the time (with his lover) and she's left all alone in her immaculate beautiful but empty house. Indeed, she herself is just like that immaculate and empty house, and the book makes her realise and reawaken the love she had for her husband.

Obviously she is a very selfish woman, just like her mother, and only now does she realise that she has turned into her, much to her dismay.

So she thinks her husband wants to meet with her to rekindle 'old times', and now she thinks that he's finally written a good book and he will start making it big as an author.....but she gets stood up. She's left sitting there on her own, surrounded by the comings and goings of happy romantic couples, waiting....and she continues to wait until closing time because deep down she knows she deserves to be stood up, she knows he's punishing her for all the hurt she did to him, and she soaks it all in, the guilt, the regret, the realisation of her aesthetically immaculate empty life. She realises what a horrible person she was and is and that she may never find true love or happiness again.

Michael Shannon was great in this as the terminally ill cop.