if you know for sure that he is talking to his ex and he is lying to you about it confront him. if he doesn't admit to it and is being defensive then you need to ask yourself if you want to be with...
Just Have fun and forget about him, you should never trust a guy unless they really love you. It takes seconds to fall in love and it takes forever just to get over him, And please add me on youtube...
Your boyfriend should be the guide to show you how to "deal" with it. You should be polite and courteous. If there are jealous feelings or you feel you cannot deal with it , you know it is time to...