I came across your discussion and felt like sharing my opinion. I may not be completely correct but it is just an attempt to initiate a healthy discussion about how peer pressure created as result of higher life standards and race of materialism can become a predictor of depression.
As we are aware that depression is increasing at an alarming rate among people in various age groups especially in young and middle adulthood so is the research about identifying its potential causes. Among the various causes established, psychosocial causes are the primary ones leading to depression and other psychological problems.
For the purpose of providing a specific answer to this discussion I would like to stick to the point of higher life standards and race of materialism as a psychosocial cause that may cause depression among people. There can be various viewpoints on that as well, some of them I have listed below:
One way of looking at it is that higher life standards and the constant motive of accumulating more money to buy fancy materialistic possessions can keep a person busy to such an extent that the person might become a workaholic down the line. With all the pressure created as a result, the person may not find time for recreation and life can become monotonous to these individuals where there is absolute lack of pleasure and sad mood might stay for long giving rise to unipolar depressive disorders like depression or even dysthymia.
The other way to look at it is to consider the social perception of an individual with which the people are largely affected these days. With all the more social media presence of an individual these days people are constantly putting themselves under undue peer pressure where they are always in a rat race to grab and showcase more to be perceived as strong, powerful, and influential by their peers. With all this, the meaning and dynamics of relationships are changing where there is less strong and deep emotional bond and people exchange feelings only to a superficial level. As a result of the lack of strong ties, people feel lonely even when they are surrounded by people and there seem to be no good social support system in times when they need it the most. All this makes life miserable for individuals and rather than having healthy peer interactions, the feeling of peer pressure take them to low mood states.
Another way of looking at the same thing is that the competitive spirit can keep a person so engrossed that the mind keeps on working all the time and is not affected by the lows and highs so as to have an effect on the mood states. Thus, depression can be a very subjective experience and can occur as a result of a combination of factors rather than peer pressure alone.
Hope your discussion is provided a justified opinion.
Thanks and Regards