Second Chances — Meredith Rae Morgan

A widowed history teacher and a soon-to-be-retired U. S. Marine each allow themselves to be talked into taking a cruise. They meet on the first day, and -- uncharacteristically for both of them -- they embark upon a shipboard romance that they believe will end on the dock at the end of the cruise. They plan to squeeze as much fun and sex into the trip as possible, and then go their separate ways.

When terrorists hijack the ship, everything changes. Forever.