Everyone will end up letting you down at some point. But that doesn't necessarily have to get you down.

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A number of years ago, a friend lamented, "People will always end up disappointing you." That was disappointing to hear at the time, during my more naive, all-you-need-is-love days.

But she was correct. At some point, everyone, no matter how close that person is to you, no matter how trustworthy that person may seem, will end up letting you down. That can range from that person not taking out the trash to judging you inaccurately to not being there for you to committing some kind of major betrayal.

If you haven't yet been disappointed by your seemingly perfect boss, friend, coworker, or significant other, then wait for it, wait for it. It will happen eventually. So, what do you do when that other shoe drops? Here are eight steps to take to reduce the impact that disappointment may have on your life:

Step 1: Set appropriate expectations. Expect some level of disappointment.

When I was in medical school, a neurology resident once told me that happiness equals reality minus expectations. That turned out to be one of the most useful equations that I learned in medical school. Having way-too-high expectations can leave you disappointed and unhappy pretty much all the time.

Those around you are in fact not you and won't think exactly as you do. They may not always know what you want and when. Additionally, they are dealing with all of the hassles, insecurities, and internal struggles of their own lives. Moreover, they're not robots, unless, of course, you happen to surround yourself with robots. Therefore, expect a certain level of imperfection with everyone, because imperfection is one of the things that makes humans human.

Step 2: Set disappointment acceptability thresholds.

Clearly, not all disappointments are created equal. The next time your roommate forgets to take out the trash, it may not be reasonable to say, "Oh, the horror. I am so disappointed in humanity." On the flip side, if your significant other cheats on you, it's OK to say more than, "Oh darn, not again. Well, guess I have to live with this little imperfection."

Therefore, it is important to determine what level of disappointment is acceptable versus not acceptable versus a major deal breaker for you. In setting such thresholds, you've got to be honest with yourself about what will really keep bothering you and, at the same time, be reasonable and not set requirements that frankly are unachievable.

Step 3: Allow yourself to feel disappointed.

Expecting disappointment doesn't mean that you shouldn't allow yourself to feel disappointed. Suppressing your own emotions can be like continuously shaking a bottle of seltzer water. Without a reasonable release, everything at some point will explode, causing even more damage. So, in the words of Madonna, express yourself. Ideally, express your feelings directly to the person who disappointed you. More on that later.

Step 4: Determine the intent, motivation, and reason behind the action or lack of action that left you disappointed.

Intent does matter. There's a big difference between a shortfall done by accident versus deliberately. The latter is clearly a more egregious offense, deserving a higher level of disappointment. Also, take into consideration the circumstances. If someone doesn't show up due to being chased by a pack of wolves, then maybe, just maybe, that person had a reasonable excuse. Of course, for some things, the actual circumstances don't matter as much. For example, cheating is still cheating even if it came right after the person ran from a pack of wolves.

Step 5: If possible, tell the person that he or she has disappointed you. Talk it out.

Ideally, you can express your disappointment directly to the person who let you down and talk it out.

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People can't fix what they don't know or realize. So, if possible, tell the person that they have disappointed you, assuming that your disappointment is justified and passes the "not acceptable" threshold. When you do so, don't approach the other person in a judgmental or accusatory manner. Instead, express how the person's behaviors affected you.

Step 6: Determine how seriously the person takes your concerns.

When you offer your concerns, Does the person simply deny, deny, deny, or does the person try in some way to correct the disappointing action or prevent it from happening again? If it's the latter, then a disappointment can actually end up strengthening the relationship in the long run.

Step 7: Give it some time, forgive where appropriate, and see the positive.

After an initial period of disappointment, that feeling may fade and be replaced with a renewed appreciation for everything good that person offers. Don't expect anyone to be perfect. Try to see the positives. A disappointment in fact can be an important learning experience.

Step 8: Shed people who keep disappointing you over and over again.

It may be OK if someone periodically disappoints you as long as they aren't always DEFCON 3 or worse situations. However, if someone is letting you down over and over again, it may be time to sever the relationship. Disappointment may be part of life, but life is too short to have a paid subscription to disappointment.