Missing You by Harlan Coben

NYPD cop Kat Donovan has never forgotten the love of her life, Jeff, even though they split eighteen years ago. Her friend, Stacy, has given her a year's subscription to an online dating site and Kat is stunned to discover Jeff's profile there. She and Jeff broke up right around the time her father was murdered. Her father was also with the NYPD and his death was always said to be a mob hit. Soon Kat finds that these two tragic events in her past are far from buried...  Missing You is another fast-paced puzzle from Coben.