I think that to get rid of it you just have to accept the relationship as a whole. Make a pro and cons list of sorts. Accept the good things as being good things, that you can remember fondly- and accept how the good things helped you or changed you. Accept the bad things as the reasons why you are no longer together- don't let the break up be your fault or his fault, but simply blame it on all the little things. Don't compare any other person to ex- everyone's different, and chances are, after getting through a break up, you will be different too- and looking for something different!
What also helps is getting rid of hurtful reminders. Delete the facebook friendship, and family and friends help. You don't need to see their attempts at moving on- it is yourself you should be focused on. Delete the phone numbers, put the pictures and presents away- at least until you can look at them without getting upset.
Most importantly- do not constantly bring up the baggage! No one else will understand. If you need to vent or reminisce, its understandable, but do that with a friend or family member- not a new interest. I honestly feel that, based on my own experience, you shouldnt attempt to find any kind of real relationship until you are at that point. Distractions and flings are fine, and can help- but I can say it took me about a year to be able to look at another guy seriously and be able to see something real with them. Time helps turn baggage into memories. Good luck!