This was one of the most enjoyable books I've read in a very long time. It's novella length, but that doesn't lessen the impact of the story. The characters are fully fleshed out and are both flawed and admirable.
Unlike far too many female heroines in currently popular books, Carrie is portrayed as an adult rather than a self-absorbed adolescent masquerading as a grown-up. Carrie makes her own decisions and choices, and she recognizes that there are trade-offs for those choices. She also recognizes that her relationship with Brian doesn't revolve solely around her. He's in it, too, and so are his accompanying responsibilities. Carrie doesn't whine or bemoan fate; she simply accepts the truth for what it is.
Brian is struggling under a burden too large for him, and like Carrie, he doesn't whine about it. He just puts one foot in front of the other and gets things done. The fact that there are more things than are humanly possible for him to do (and that those things have to be repeated day-in and day-out) is slowly overwhelming him. Ms Rivers does an excellent job of conveying not only Brian's determination but also his quiet despair and ever-present guilt.
What begins as a stolen, self-indulgent hour each week quickly blossoms into a deeper connection, with all the associated difficulties and pitfalls. There are no Big Misunderstandings here, no cliched plot twists. There's only two adults having an adult relationship, and it's a lovely thing to behold.