text: From a guys perspective and also one that is going through the same thing, be harsh, be rude, and most of all be upfront. I made that mistake of being the "nice guy" with my ex-wife and found that in the end I gained nothing and lost everything. After you tell him like it is, then change your number, for me it was the best thing I could have done. And if he continues to call you then you may need to take the next step and take legal action. Good luck, be strong, and don't let some bonehead get you down.