ok this is a hard one my view on this topic would be just hang out with ur friends try to stay away from any thing that reminds you of her/him
than once you feel a little better listen to some chearful songs like if u live in america the all american rejects the song i listen to is move along
im the type of of person that cant really forget if your like that just dont think about it for a few days and hang out with ur friends and eventually u,ll get over it