Think of other things and other ppl instead. Try going out with your friends and new people. Try out new hobbies, whatever grabs your attention and just have fun with them.
The quickest way would probably be to fall in love with someone else, although this can be hard to do on command. Except for that, the best advice is probably to go out and keep busy. There are no miracle cures that I know of, it takes as long as it takes, so the best one can do is keep living and not spend too much time dwelling on it.
Get amnesia.
Try thinking of something else or doing something else. It also helps to go out with friends and having fun.
