You, Again by Kate Goldbeck

After a confrontational first meeting (at the apartment of the woman they are both sleeping with), Ari and Josh never expect their paths to cross again, but years later, as they're both reeling from ego-bruising breakups, a chance encounter leads to a surprising connection: friendship. Turns out, spending time with your former nemesis can be fun when you're both too sad and miserable to hate each other. And as odd as it seems, they become friends-without-benefits, finding comfort in late night Netflix binges, swiping through each other's online dating profiles, and bickering endlessly on their phones across boroughs.

It's better than romance. Until one night, the unspoken boundaries of their platonic relationship begin to blur...