Your happiness depends on three things, all of which are within your power: your will, your ideas concerning the events in which you are involved, an… - Epictetus

For it is indeed pointless and foolish to seek to get from another what one can get from oneself. [32] Since I can get greatness of soul and nobility of mind from myself, shall I seek to get a patch of land from you, or a bit of money, or some public post? Heaven forbid! I won’t overlook my own resources in such a manner. [33] But if someone is abject and cowardly, what on earth can one do for him except write letters for him as though on behalf of a corpse, ‘Do please grant us the corpse of this man and a pint of his miserable blood’; [34] for in truth such a person is merely a corpse and a pint of blood, and nothing more. If he amounted to anything more, he would realize that no one suffers misfortune because of the actions of another.

There is but one way to tranquility of mind and happiness, and that is to account no external things thine own, but to commit all to God.

What are you? A human being. If you think of yourself as a unit apart, then it is in accordance with your nature to live to old age, to be rich, and be healthy. But if your view of yourself involves being part of a whole, circumstances may make it right for you to be sick, go on a dangerous journey, endure poverty, even die before your time. Don't complain.