Blind Faith by Judith Pella

As a fledgling artist and a single mother, Irene Delaney has had her share of hardships, and the shocking news of her ex-husband's mysterious death threatens to crumple her newly found contentment. As the events surrounding Greg's death unfold, Irene discovers a shadowed past that includes Joel Costain--a successful attorney who is deeply intent on finding Greg's murderer. As Irene soon realizes, Joel is just determined to whittle away the guard around her heart.