Disappointment is ranked as the third most commonly experienced emotion, following love and regret. Psychologist Susan Krauss Whitbourne, Psychology Today

Whitbourne cites “Disappointment Theory,” which states that “we experience disappointment when a situation that has an uncertain outcome ends up producing a result that is worse than we had expected. We’re most likely to be disappointed when we were seeking a positive outcome, when we felt that we deserve this positive outcome, when the failure to achieve that outcome is a surprise, and when the failure is outside of our personal control.”

Basically, then, it’s about expectations and how we interpret their lack of realization.

Blessed is he who expects nothing, for he shall never be disappointed. Alexander Pope

Having no expectations is the easiest way to avoid disappointment, a challenging path some do try to take. Buddhist teachings (Buddhanet), for instance, define “right view” and “wrong view”: “Wrong view occurs when we impose our expectations onto things; expectations about how we hope things will be, or about how we are afraid things might be. Right view occurs when we see things simply, as they are. It is an open and accommodating attitude. We abandon hope and fear and take joy in a simple straight-forward approach to life.”

Another option is to look at lowering one’s expectations. With more appropriate expectations, we have a better chance of meeting our goals. Hence, a lack of disappointment.

Although we can achieve this through conscious effort, sometimes we also do it instinctively. One example, reported by Nina Elias, Prevention, has to do with awaiting important results such as grades or medical diagnoses. What tends to happen is that we engage in a psychological process known as “sobering up”: our expectations lower temporarily just as we’re about to find out, which is self-protective.

What if we can’t lower our expectations and thus wind up disappointed? A crucial first step involves facing it, which psychologist Mary C. Lamia believes is too often avoided. From a Psychology Today post:

In my psychotherapy practice I have found that people avoid disappointment far more than many other emotional experiences. Disappointment comes with finality–the recognition that you don’t have, didn’t get, or will never achieve whatever it is that you wanted. You might experience being angry with a parent, spouse, relative, employer, or friend, and that is far easier to feel than your disappointment in the relationship. Disappointment forces you to admit that you did not get what you wished to have, and it is actually easier for you to protest with anger than it is to encounter your sadness about the course of events. In an obstinate way, anger will allow you to continue idealizing what could have been while consciously denigrating it, and you will hang onto it only because it’s what you needed at the time. Disappointment accepts reality.

So, now that we’re accepting reality, what next?

Disappointment is merely an unmet expectation, it’s only when you imbue it with negative meanings that it becomes painful. Dr. Mark Goulston, Psychology Today

As stated in a post (use the link above) by Dr. Goulston, some cognitive tweaking enables you to turn “dysappointment,” a painful place to be, into disappointment handled with “poise and aplomb.”

So the next time something doesn’t happen that you expected, instead of thinking, ‘That shouldn’t have happened,’ think, ‘That’s just one of the things that happen that I don’t like or didn’t expect and furthermore if I handle it well, it’s a tremendous opportunity for poise.’

Below, an infographic on “The Psychology of Disappointment” gives a good deal of additional info:

Source: Best Psychology Degrees