1. Realize that even the best of relationships can come to an end. I think we have a tendency that once a relationship ends, we throw the whole thing into question. To think that its demise was a sign that what you thought was "real" (i.e.—your time together, love, etc.) wasn't. But the truth is that good things—including relationships—can come to an end.
2. Recognize what lessons the relationship taught you. Regardless of whether it was short or long, contentious or amicable, each and every relationship has lessons for you to walk away with—lessons that will help you know more about who you are leaving it than when you entered it.
3. Rationalize your way into positive thinking. Look, we all feel terrible after it's over, but sometimes the only way to really get better is to sort of, well...fake it. Think positively even if it feels untrue, and soon enough, you won't have to force it at all. Create your own reality.
4. Refrain from playing the blame game. If you're really serious about getting over your ex and moving on, you won't wallow in who was right and who was wrong. Instead, take your blame (or guilt, as the case may be) and focus on turning it into a lesson to be learned (see #2).
5. Remain open to the possibility of another. It can be hard to imagine after a breakup—meeting someone else and starting all over again. In fact, you may not be able to stomach the idea at all. But in time—and by following the four steps above—you will meet another. And this time, it will be better than before because you've done the hard work necessary to leave your last relationship behind, move on with the next, baggage-free and all.