We can change, and that's why our circumstances change. There's no permanent win or loss. It comes and goes.
Acknowledge the effort you put in, instead of the goal you achieve. Goal is simply a limit you set, but it is during the journey you grow the most.
Stop fretting over short term frustrations.
Meaning in life isn't a treasure chest waiting to be found. Meaning in life is an invention that an inventor discovers by themselves.
Life's always meaningful, you just need perspective to see it. Change your perspective and life will be enriched.