Don't demand that things happen the way you want them to. Instead, want them to happen the way they do happen. Then you'll be fine.
Demand not that events should happen as you wish; but wish them to happen as they do happen, and you will go on well.
The Enchiridion, Section 7 — In Plain English
Think of life like a voyage. When your ship stops at port and you go ashore to get water, you might pick up a shell or find a mushroom along the way. That's fine. But keep your attention on the ship. Stay alert for the captain's call. When he calls, drop everything and run back. Don't make him drag you aboard like a stubborn animal. Life works the same way. Instead of shells and mushrooms, you might be given a spouse or children. There's nothing wrong with enjoying these things. But when the captain calls, run to the ship. Leave everything behind. Don't look back. And if you're old, don't wander far from the ship. You don't want to miss the call.
As in a voyage, when the ship is at anchor, if you go on shore to get water, you may amuse yourself with picking up a shellfish or a truffle in your way, but your thoughts ought to be bent toward the ship, and perpetually attentive, lest the captain should call, and then you must leave all these things, that you may not have to be carried on board the vessel, bound like a sheep; thus likewise in life, if, instead of a truffle or shellfish, such a thing as a wife or a child be granted you, there is no objection; but if the captain calls, run to the ship, leave all these things, and never look behind. But if you are old, never go far from the ship, lest you should be missing when called for.