Some words are hard to say. Take "I'm sorry," for instance. If you spill somebody's coffee, those two words roll right off your tongue. But if you've really stepped on somebody's toes (and especially if they've stepped on yours more), apologizing can look like climbing Mt. Everest. "I'm sorry" might be hard work, but it sure is easier than the alternative.
“Remembrance of wrongs is . . . poison of the soul, worm of the mind, . . a nail stuck in the soul, pleasureless feeling cherished in the sweetness of bitterness, . . unsleeping transgression, hourly malice. . . ." St. John Climacos (A.D. 590)