Kiss of the Shadow Man — Maggie Shayne

The husband:
Dylan Rossi had bitterly agreed to the divorce his ice princess of a wife wanted so badly. But that was before the accident that had stolen her memory-of him, of their awful marriage, of much, much worse...

The wife:
Someone was trying very hard to kill Caitlin Rossi, a wealthy woman who'd made enemies she couldn't remember - enemies that included the handsome husband she feared as much as she desired...

The marriage:
Once separate bedrooms had kept the Rossis apart. Now only the continued loss of Caitlin's memory would keep them together...