It is applied often enough to animals, we marvel at how fast they adapt to changing environments. How a once wild tiger can be trained to perform tricks and amazing acrobatics. How a parrot can speak and ask its owner for food or water. We are impressed by these adaptations but fail to carry the comparison to our own friendships and associations.
The bottom line for us is that we generally live up to the expectations of the people we are around. If your boss thinks you are a very dependable person, you tend to be more dependable than you otherwise would be. If your friends think you are the funniest person they know, you tell jokes and act funny more often than you would otherwise. So far this sounds pretty harmless but there is a darker side.
If someone's boss thinks they are incompetent, or incapable of completing a task that person often lives up to that expectation by failing or underperforming. If your boyfriend is jealous and believes you are seeing someone else, you are actually more prone to engage in that behavior based on his expectations. If your friends think you are a dreamer with no real future... well you see where this is going. So, what can we do?
The most important thing to be gained here is awareness. Be aware that the people around you have a good deal of influence on who you are and who you will become. This means that there will be times when ending a friendship with a person who does not think highly of you will be the best thing you can do for yourself. This also means that if you surround yourself with people who respect and admire you, you are more likely to live up to those expectations.
So take stock of your life and identify those people who are negative influences. Weed as many of them out of your life as possible. Also begin to seek out positive influences when meeting new people at parties or work functions. Try and add one or two positive influences every week and see how quickly your outlook and situation improves.