Kalter Himmel (1992)

While on holiday in Mexico, unhappily married Marie Davenport summons the courage to tell her unknowing husband, Alex, that she is leaving him for her lover. But before she delivers the news, Alex is involved in a boating accident – and Marie is unsure whether he's dead or not. Faced with supernatural events, Marie turns back to Catholicism and seeks the help of Father Niles and Sister Martha.