Give yourself a mourning period for the loss - three months ish. Really feel sorry for yourself during that time. Wallow in it as much as you like, lean on your mates, get hammered, listen to the Smiths, whatever works for you.
Then when the time is up, snap yourself out of it, hit the town/ dating sites whatever, and get some new action. You will be so sick of feeling sorry for yourself at that point that there will be a window of opportunity for you to move on - take it with both hands. I bet you won't even feel a pang for your lost love before 12 months is up.