If you have broken up recently and your ex calls you then try to be short and reduce the conversation to the extent that you can. Right now after the break-up what you require is space. You are not yet in the right frame of mind. You are probably upset, angry and shocked. So if you try to talk to your ex in this frame of mind, chances are high that you will start venting or getting into those old issues responsible for the break up in the first place. There is absolutely nothing to be gained by repeating the same topic again – it will hurt you lot more than it will help you. So stay away from the phone. If you work with your ex and do not have a way to avoid then simply make it a professional relationship to the extent required. Do not avoid them more than you need to but at the same time do not be with them any more than you need to. If you want to get your ex back, this is something you would want to keep in mind throughout the process of trying to win them back.