Have you ever stopped to think how much our image of ourselves effects what we do and don't do. I came up with a theory about this phenomenon. We blame our social situations for hindering our "individuality" and "freedom" to do whatever we want without judgement. Though this may be a part of it, for a lack of a better term I believe that we are our own worst enemy.
We see ourselves a certain way, and dare not stray from that self image. Whether consciously or subconsciously everybody works to be a certain kind of person. Everybody falls into some kind of stereotype: prep, hipster, tomboy, alternative etc. If a person is told something about themselves for long enough they begin to believe it. As is human nature. It's this human nature that causes us to become stuck in our own social identity.
We willingly or unwillingly embrace that. Over time it becomes second nature and a comfort to us. We live in that identity from day to day not thinking much of it. That is until someone wants to try something new. They find that the identity is a serious road block.
We run into the "I can't do that because I'm me" phenomenon. Where we won't do something because a ___(fill in the stereotype) could never be caught dead doing that. Our mentality narrows our field of vision and we disallow ourselves to do a certain thing(s) because we would be in some way betraying our label. Spending multiple years around the same people also keeps us in place. Because subconsciously we know what to expect from each person in our lives and it becomes weird if one of those people steps out of their typicality.
But, there is a way that this constriction can be solved. It typically involves being in completely new situations (ie high school to college where you don't know anybody). The beauty of being in a new place is that nobody has learned what to expect of each other yet. We also learn that we can open our field of vision. It takes getting rid of the "I could never do that because I'm me." Granted that is easier said than done but it's pretty cool when it does happen.