Winter in paradise : a novel
(Book)

Several internet sources identify this as book 1 in the Paradise series.

Irene Steele's idyllic life-house, husband, family-is shattered when she is woken up by a late-night phone call. Her beloved husband has been found dead, but before Irene can process this tragic news, she must confront the perplexing details of her husband's death. He was found on St. John island, a tropical paradise far removed from their suburban life. Leaving the cold winter behind, Irene flies down to the beautiful Caribbean beaches of St. John only to make another shocking discovery: her husband had a secret second family. As Irene investigates the mysterious circumstances of her husband's death, she is plunged into a web of intrigue and deceit belied by the pristine white sand beaches of St. John's. --,(source of summary not specified)