Have you seen this picture? This is actually a fact that always happens and will always happen.
I've thought about this for a long time, observed many people from various lifestyles, and realized that this kind of thing is actually happening.
Maybe if you have enough source of happiness like a good relationship with families and friends or a good environment, then you won't get that feeling. But if you're not that lucky?
I found valid information about this and based on research from here.
"These findings indicate that wealth is not unequivocally associated with happiness," said Piff. "What seems to be the case is that your wealth predisposes you to different kinds of happiness. While wealthier individuals may find greater positivity in their accomplishments, status and individual achievements, less wealthy individuals seem to find more positivity and happiness in their relationships, their ability to care for and connect with others."