Are Catholic works really difficult for many people to deal with?
Apparently so, only because people have lost all notion of objective reality and do not think logically. Even if you present a logically cogent apologetic argument in defense of the faith, some people will still not assent to it because it contradicts the caprices of self-centered passions and habits.
They prefer emotion over reason, opinion over fact, "spiritual experience" over true religion, &c.
Ultimately, it is the cult of self, which is an idolatrous affront to God, Whom both faith and reason prove to exist and to claim all our reverence and love.