is there anything I can do? my boyfriend's ex keeps tomenting him!

they were married for 15 years but together about 25 years. no children but a blended family. it's over, really over and she can't over it. she toments him by email, sends emails to all of their mutual friends, says vile things about him, and on and on and on. in one email she tells him never to contact her again, then she sends three more emails of her own. he has tried to be civil with her, he wants them to be friends. She uses religion to torment him - calls him Lucifer and Judas and wishes bad health on him. He doesnt know how to handle it. so much is involved as they have many common friends and shared a long relationship. Is there anything I can do? or do nothing? help!