I Wish I Knew Then by Jessica Peterson

My grandmother has a saying: what’s done in the dark always comes to light, especially in small towns with big secrets. And I was hiding the biggest secret of them all.
Every summer I spent growing up at my grandparents’ coastal estate was the same. Same cousins. Same chaos. Same long golf cart rides along the beach.
But everything changed the summer I turned eighteen, when my grandparents’ new housekeeper moved in with her son, Riley. With his big personality and head-turning looks, he was the local heartthrob.
We fell in love instantly. Riley was my first everything. First love. First time.
And my first heartbreak when he dumped me at the end of the summer.
Ten years later, I’m back on the island for my best friend’s wedding as her maid of honor. Who’s the first person I literally stumble into?
Riley Dixon. Even worse? He’s the groom’s best man, and a self-made billionaire to boot.
Being forced to spend an entire week together for wedding festivities quickly leads to more: hot hate sex, late nights of sneaking out, and unexpected revelations. The boy I knew a decade ago is gone, and the hate becomes…something else entirely. And I begin to wonder if Riley is hiding some secrets of his own.