The only men who achieve great things are not concerned with their happiness. They seek pain and they seek discomfort because it is only through pain and discomfort that we tear the muscles—literal and figurative—that make us stronger.
It is the supreme sin of our world to seek happiness above all else and to associate that happiness with unhindered submission to and expression of our baser passions. No one should be fat-shamed because people should not be judged for their gluttony. No one should be slut-shamed because people should not be judged for their lust. Et cetera.
A true love of people, however, requires that we not play along with the delusions of those who shackle themselves to happiness. They choose slavery and their choices should not be allowed to affect (infect) others, most of all ourselves.
We shouldn’t primarily concern ourselves with the sins of others, obviously, but with eradicating those sins within ourselves and delineating a border through which the whims and fancies of the modern world are not allowed to cross. Where the world loves its happiness, we love holiness. Where the world seeks pleasure, we seek pain. Muscle grows stronger after being torn by the weight of iron. The soul grows stronger after being torn by the weight of suffering.
Seeking pain is seeking holiness. Seeking discomfort is seeking holiness. Seeking suffering is seeking holiness. That being the case, the mind should be primed to accept this fact: our misery comes not from the bad or evil that befalls us, but from not perceiving the "bad" or "evil" that befalls us as the neutral opportunities that they are. All circumstances, whether we initially perceive them as good or bad, are opportunities for good. They are opportunities for holiness. And how they are approached, how they are acted on, can mean the difference between you the saint and you the sinner.
Seeking pain is difficult and, yes, it is painful, but ironically less so than a virtueless life of pleasure-seeking, a bondage to "whatever makes you happy."