Welcome to “First Chapters,” Cosmo’s column where we shine a spotlight on newer authors who you are definitely going to be obsessed with. And what better way for you to get to know them and their books than with an excerpt of their new release. This round, we’re highlighting Nayantara Roy ’s Sisters of a Halved Heart , a new honest and compelling novel that follows two sisters after one of them does the unthinkable, leaving their relationship in pieces. As one returns to New York, they have to come to face the truth between what happened between them. Here’s some more info from Algonquin Books : The electric story of two sisters and an unthinkable betrayal. Mira Guhathakurta is a poetry editor at a distinguished literary magazine in New York, a dream job that has given her nearly everything she’s always wanted. And then she reconnects with Jack from college—kind, funny, intelligent Jack—and suddenly Mira feels as if she might have found her soulmate.…