You're the One that I Haunt by Katie Jung

To save her best friend and lifelong crush from his family’s deadly curse, Libby must team up with (and try not to catch feelings for) a handsome ghost only she can see

Libby Lakoski has two major problems. First, she’s secretly in love with her best friend, Carter Coldwell, and second, he’s marrying someone else. Carter’s the only person who has ever made Libby feel chosen, and sure, his fiancee is a British diamond heiress, but Carter and Libby have years of shared history and longing looks between them. Not to mention, Libby is the only person Carter trusted enough to tell about the dark magic that plagues his family.

But then a third and related problem presents itself—or, himself. Trip Coldwell is Carter’s handsome, smart, flirtatious cousin who also happens to be… a ghost. Trip’s “unfinished business” is to break the Coldwell curse, but the solution hinges on Libby encouraging Carter to allow his wedding to proceed. Unfortunately, Libby is the only person who can see Trip, and her objective is the exact opposite. Can Libby put aside her pining for Carter and work with his hot and not-quite-living cousin to save both men?

As they follow a trail of clues across New York City, Libby finds herself questioning just how much Carter reciprocated her friendship, feeling perplexed by a growing attraction to Trip, and fantasizing about actually touching him. With the countdown to the wedding in full swing, Libby must choose between saving the Coldwells and holding tight to her own happily ever after.