It's about a woman who meets a guy online (I think a dating site, but it might've been some random site), and then goes missing. Her best friend, who I think is somehow involved in law enforcement, leads the search for her.

For some reason I thought it was Every Secret Thing by Laura Lippman, but reading the synopsis, that's about something totally different. I think it has a similar title, though.

Anyone know what it could be?