In spite of the oft time proclaimed desire to be an individual and march to the beat of our own specific drummers and the acclaim that often brings the desire to one of the accepted components of the societal crowd often overwhelms all other desires when peer pressure is applied. Apparently human nature is such that individuality is only a positive motivation up to a point. Go too far, stretching the limits of tolerance, can only bring retribution of one negative sort or the other down on the offending head.
With the engendered feelings of self loathing that often results from peer pressure when it's particularly severely applied comes the realization that being ostracized just isn't fun. Standing up for oneself and staying true to ones codes can be a difficult proposition at any age but particularly when one is younger and still trying to find oneself it can be all too devastating.
Peer pressure is applied with particular enthusiasm, at least in our culture, when it has to do with sexuality and dating. Dating comes with its own wealth of pitfalls since emotions and perceived inclinations based on societal standards aren't a defined science. There is also the aspect of religion, age, gender perception, inexperience and hormone prompting add spicy ingredients to the dating stew. Peer pressure heaped on top of that just makes it all that much harder when an attempt is made at staying true to ones codes.
Peer pressure is pressure applied by those of the same approximate age. Men are constantly bombarded with the idea that they "have to get some" and if they don't they are made to feel inadequate by their peers. Therefore if they have religious or other reasons why they might not want to have sexual interactions with a date they are made to feel inadequate by their friends based on the age old premise that men need to have "conquered" the female in their life in order to have their existence justified. This mindset goes against many religious teachings.
On the opposite side of the coin, staying true to ones codes may actually provide the means by which to free oneself from being subservient to the peer pressure being applied by those around one. If one has convictions that transcend the ridicule heaped on by teasing, mindless people then one doesn't need to pay any attention to those attempting to control by using tactics such as peer pressure.
There have been a variety of rules and regulations to do with sexual interactions that have been applied both by religious groups and governmental groups with the intent of maintaining control over the society. Peer pressure, in part, grew out of the people's attempts to keep those who might stray and get into trouble from doing so. If they weren't supposed to engage in sexual interactions before marriage and would be ridiculed or worse if they did there was a faction of the population that would apply peer pressure to keep the worst case scenario from happening.
If one individual can manage to embarrass another in sufficient degree then that first individual may not pursue the course of action they were intent on. It's amazing the power that others opinion can have over the activities of others. Sometimes how one is perceived is more important than anything else. Hence the usefulness of peer pressure when trying to dissuade someone from following a course of action that is not seen as being suitable, or vice versa.
In the modern day and age that we live in now a lot of that peer pressure is exerted through the standards set up by the media and advertisers intent on separating us from our hard earned money. This is peer pressure nonetheless because we are expected to dress, act and transport ourselves in a manner appropriate for our age and/or sex and if we fail to do so our peers will look askance at us.
We must comply in order to be accepted as one of the gang and therefore privy to the inherent privileges, for example a wonderful sexual relationship resulting from successful dating habits.