Let me begin by saying that this was one of the most heart-wrenching books that I've read in a long time. I love YA contemporary for the fact that you get some books that absolutely rip your soul to shreds, and for me, One Moment was one of those books. Summer's almost over, and Maggie and her friends are celebrating at the gorge when a dare goes horribly wrong, leaving Maggie's boyfriend, Joey, dead and with Maggie not able to remember what happened. The dynamics of her friendships are changing as they all learnt to cope with their grief, especially Adam, Joey's best friend, who is drifting away. As Maggie learns to cope with her own grief, and the suppressed memories that she can't remember, secrets about her boyfriend start to come out, and Maggie tries to figure out what really happened that day at the gorge.Maggie, as a character, is a character I can relate to so well. She's human, she has flaws - she's stubborn and often dwells on the past and the 'what ifs' and wonders if she could have done anything different in her life. She's grieving for Joey, the boy she thought was perfect, in more ways than one. At the start of the novel, after Joey's death, it's so painful to see her go through life without the one person who kept her strong. Maggie and Joey had been dating for two years, but the crush goes way back when, and the romance fits in perfectly with their close knit group of friends. Yet as time moves on, and her memories start to come back, Maggie is questioning whether or not Joey was as perfect as she made him out to be, especially when the secrets start coming out. And this is where the story picks up, and takes you for a ride. The start? It's like the beginning of a roller coaster, where you are cruising along softly, and then all of a sudden - you're dropping down, head first, only to be slammed back up again. And this is what One Moment is like from that moment on, as the secrets are spilled out and friendships are tested.Please note the next paragraph is a spoiler - to read my thoughts, just highlight the blank looking bits. If you haven't read One Moment yet, don't read it unless you want to be spoiled!One of the things I liked the most though, is how this is a different angle to a very typical YA contemporary romance. Usually we are reading from the perspective of the girl who has fallen in love with the unattainable boy, but this time, the roles are reversed. Maggie is the girlfriend, the one who finds out she's been cheated on, and the girl is not only meant to be one of her best friends, but she also has a backbone and defends her secret relationship with Joey. I often get sick of the "I've fallen in love with my best friend's boyfriend" triangle, but I loved this one. It was perfect.This is one roller coaster of a book. This was emotional, it was real. You'll want to cry alongside Maggie, you'll want to yell at her for not opening her eyes. I felt like a ghost, as if I was actually witnessing all the events unfolding in front of me and not being able to stop them. Kristina has an amazing writing style that will keep you on the edge of your seat, pulling you back in for more and more and you won't want to tear your eyes away, not even to grab a tissue.