I think that the most important life lesson anybody should learn is this: you do not need to suffer. And although to endure suffering is a very Christian mantra, and sometimes an admirable trait, one must have enough self love to identify conditions and circumstances that one can choose to not be tangled with.
You don't have to put up with that moody roommate. You don't need an emotionally abusive boyfriend. Or an inconsiderate job. Master the art of putting a fine line between what's tolerable and what's not. Love your life by the choices you make. The best ones are those that you can live with wholeheartedly - no negative energies; just pure, unadulterated happiness.