A few quotes from Marcus Aurelius.

Be like a rocky promontory against which the restless surf continually pounds; it stands fast while the churning sea is lulled to sleep at its feet.

I hear you say, "How unlucky that this should happen to me!" Not at all! Say instead, "How lucky that I am not broken by what has happened and am not afraid of what is about to happen. The same blow might have struck anyone, but not many would have absorbed it without capitulation or complaint." (IV. 49, trans. Hicks)

If thou art pained by any external thing, it is not this that disturbs thee, but thy own judgment about it. And it is in thy power to wipe out this judgment now. (VIII. 47, trans. George Long)

A cucumber is bitter. Throw it away. There are briars in the road. Turn aside from them. This is enough. Do not add, "And why were such things made in the world?" (VIII. 50, trans. George Long)

Put an end once for all to this discussion of what a good man should be, and be one. (X. 17,[13])

Soon you'll be ashes or bones. A mere name at most—and even that is just a sound, an echo. The things we want in life are empty, stale, trivial. (V. 33, trans. Gregory Hays)

Never regard something as doing you good if it makes you betray a trust or lose your sense of shame or makes you show hatred, suspicion, ill-will or hypocrisy or a desire for things best done behind closed doors. (III. 7, trans. Gregory Hays)

Not to feel exasperated or defeated or despondent because your days aren't packed with wise and moral actions. But to get back up when you fail, to celebrate behaving like a human—however imperfectly—and fully embrace the pursuit you've embarked on. (V. 9, trans. Gregory Hays).