Siren's Song by Yasmine Galenorn
When the fog rolls in from the sea, sometimes ghosts from the past follow it...
Sandy's under attack. First, she's almost mowed down at the supermarket, then her new beach-front oyster bar is destroyed right before its grand opening. But when she's found in a coma, the danger heats up as parts of her dreaming world escape into reality. Now, Maddy, Aegis, and Max must find the cure for the mysterious disease Sandy is suffering from, before she's permanently trapped in the realm of dreams.