3. Cut the cord. See 1 and 2. Being cold and resolute means you make it difficult to impossible for Loser to contact you. Delete his email address and block his number from your phone. Unfollow him on Twitter and block him on Facebook. Make sure your privacy settings on Facebook and other social media are such that he can’t see photos of you out frolicking with friends. If he emails you anyway, delete the messages prior to reading. Don’t go to the same places you used to go together. Don’t inquire as to his well-being with your mutual friends, as it will get back to him that you did. (“She asked how I’m doing! She still cares!”)