For me, it's to come face to face with the realization that in many cases there will be no justice for certain aspects of our lives. "The winner takes it all. The loser standing small..."(Abba Song).
Leonard Cohen's song: Everybody knows:
Everybody knows that the dice are loaded
Everybody rolls with their fingers crossed
Everybody knows the war is over
Everybody knows the good guys lost
Everybody knows the fight was fixed
The poor stay poor, the rich get rich
That's how it goes
Instead of being depressed that we may never experience justice, we can TRANSCEND the state of injustice. The only transcendence there is when justice is impossible in your own life is to be certain that you NEVER commit the same injustice to your fellow human being and that you try in everything you do throughout the day to bring about even the tiniest of just actions - if someone hurts another person with their words, be the person who next uplifts that hurt person; if someone doesn't pick up after their dog, instead of walking by, YOU pick it up; if someone seems to be the only one impatient in line, let them go ahead. An accumulation of tiny reversals of injustices that you see in your life can bring about trancendance.
If you're able, do the BIG reversals of injustice. Find a group like Oxfam who tries to get food and shelter to people in war torn areas or helps with new farming techniques, and contribute to them - things like that.
The movie "Manchester by the Sea" illustrates that there are some injustices that cannot be reversed. You can argue that the main character was at fault, but he did what many people do everyday and never receive the same punishment from the universe. There was NOTHING that could reverse that injustice that life presented to him. There is only the ability to cope and transcend.
My lovely family of 20 yrs was destroyed when my husband left. He told me I was a "wonderful wife and a wonderful mother". The sense of injustice is searing in me because only he and I know that it didn't have to be that way - that my child didn't have to be emotionally affected for the rest of her life in that way. There can never be justice for me for what the other woman wrought in my life. I can only try to transcend the pain by doing whatever I can in my life to see that this doesn't happen to someone else - to tell my story and reveal the pain and vow to not inflict pain on another by my actions. Facing the truth about injustice brings peace.