The Singles, by Meredith Goldstein.
In the top right-hand corner of the board was a list of names written in bright red ink and all-capital letters: "HANNAH MARTIN, ROB NUTLEY, NANCY MACGOWAN, VICKI CLIFFORD, JOE EVANS."
Above the same, in the same crimson print, Bee had written the word "SINGLES."
They were the only guests to RSVP for Bee's nuptials without using their plus-one invites, and now they were the only names Bee hadn't yet placed on her seating chart.
The Singles end up interacting at the wedding and some interesting pairings take place. Each person has a story of their own to tell, and although the reason they are all gathered in Maryland is because of Bee, the focus of the novel is not on her, for the most part, but on her friends and the people who are at the wedding.
I could see this being a movie, too (and one of the characters, Hannah, is a casting agent, and likes to cast people as she meets them), although it might end up being a rom-com even though the source material is more serious throughout.
4 stars out of 5.