I think he is just worried on about how you will react. Break ups are a natural thing he is ready to let go and that is okay. One day when the time is right you will find someone who is right for you!
My boyfriend wont tell his ex about his new girlfriend (me) what do I do?
Why would you want him to tell his ex about you? If they are over he probably won't talk to her and if he does they probably are not over unless it's been a great deal of time
That's ridiculous, why do you want him to tell her about you (his new girlfriend), I guess instead of pushing him tell her, you should help him forget her and so this may make your love strong. Instead if you tell him to tell her about his new gf (you) then maybe they will have a fight and then. It may get solved and then they may become good friends and so this may cut you off the relationship with your bf so change your decision before you loose him!