If you embue every moment and aspect of your life with meaning then all you see is punishment and reward, seemingly dealt to the least-deserving people. But if you recognize it for what it is, a tiny, meaningless flash in the middle of an incomprehensibly huge explosion, you can see that what meaning it holds is yours to determine. Just because life will shit on you sometimes doesn't mean you need to help it take down its pants and squat.
How wonderfully said.
Acceptance of life as it comes without seeking to stamp meaning on it - that's definitely the key. If you try to impose your expectations on life, it will disappoint you, frustrate you, and you'll live in a miserable state of mind, trying to grasp onto something that can't be grasped. I'm reminded of Taoism, and its emphasis on harmonious yielding, and of achieving success through surrendering the desire to do so. Channeling your will into harmony with the natural patterns of the universe rather than railing against them, and seeking a means of applying oneself in a non-assertive way to maximise happiness and success.