honey, you are so young! (ok, we are as young as we feel ) don't despair, with or without him you will CAN be happy, you are just able to see this now because the pain is too great. Hollywood has messed up our minds about love, about "the one", i also believed stbx was the one for me and likewise. I now believe that one can be as happy if not even more with another person. I know this is not what you want to hear, but in order to let go of the pain that burns you you must face the fact that you can be happy if he never comes back. Once you are free from that anxiety you will be able to think clearly and get a reign on your emotions when you see him.
It is a rollercoaster, we all go through it, one day we feel like we can do it all, next day we are down low. The important thing is that you keep moving forward.
Be not afraid...I will repay you for the years the locusts have eaten Joel2
30something 2kids survivor of S, MLC, A, D I have peace in my heart, at last.