I've read 22% of The Layers by Candace Austin.

The Layers - Candace Austin
This book is so bizarre, guys! Everyone remembers their past lives! There's a new social network out called TheLayers.b4u which is like Ancestry.com and Facebook combined! Anyone can join and share their past life memories and connect with others from their past lives! I am really excited to finish this, hence the many exclamation points!
In a world that remembers past lives, he remembers her -how he loved her, how she killed him.
Since the Unveiling, most everyone struggles with memories of past lives, but 19-year-old David Kiplinger struggles more than most, more than anyone. When TheLayers reveals his 68 lives, shattering the record set at five, he becomes the story of the century, an overnight celebrity, and the world looks to him for an answer to the burning question—what is the point of living? 
For David, the answer has always been her--the girl he knows will come, the one he will love unconditionally, the one who will kill him.
When he’s teamed with Holly Stone to write his autobiography, he’s sure that he’s found her again, but rather than run, he relies on the signs he’s been given that this life will be different. And that’s when bad things begin to happen. 
With their lives suddenly in danger, they’re secreted away to a North Carolina mountain retreat where they tumble even further into a tangled web of passion and apprehension, love and suspicion. If they’re to have a future, they must first unravel the mystery of their past and determine once and for all if Holly is the love of his lives, his angel of death. 
Much to the couple's dismay, the fates hold true to their trickster form when all revelations come to pass on international television, setting the world on a countdown to David’s twentieth birthday—a birthday he may not live to see.