There is no "moving on". Once you love someone, love is forever. Once you have loved you remember, everyday and every night. You cant go back that is all. The magic is still there, preserved in amber. That first holding of hands, that first embrace, that first kiss, that first promise of this life and all future lives, in the dimension called once upon a time.
Once in a while, you uncontrollably make the baby sounds you made for him. Once in a while, you call out his name. You are no longer you, he is no longer him, you and him were once one cloud, and now you are separate raindrops and rivers, unrecognizable, never to meet.
There is no moving on, love is forever. But you expand, you learn, you live through the devastation, you survive, you will become more loving and contented, you play, you learn to be happy again, and you keep that special space for him, never mind nothing will ever be the same, never mind the rest of the universe.