I don't know how much headway you'll make with regards to dealing with your mother because people are difficult to change, but as far as getting rid of the calls/emails that are bothering you right now, maybe have another male answer the phone when this person calls you so that your ex is thrown off by thinking he called the wrong number? Maybe that will stop him from calling. E-mails I think you just have to ignore, unfortunately, unless you want to go to the trouble of changing your email address. You could change your phone number, too, if it gets threatening or something, but I'd try first to have someone of the opposite sex and/or who sounds nothing like you to answer the phone and tell him it's the wrong number. Hope this helps.