If you broke it off with her, grow up and move on. There is no reason to stay CLOSE friends with an ex, shes an EX FOR A REASON.

I stay CORDIAL with my exes for the most part in the event that i might run into them, but i dont stay their friends nor call them ever.

Shes an ex for a reason, cut her off, time to move on. Either that or break up with the current GF. Shes right, you have to choose, cant have it both ways.