And then accept it. And move forward.
At one point in your life, you have to revisit this even and go through the pains to face it and own it. Accept that it happened, don't deny it. Denying it does not change the past but it changes your future. Grieve over the disappointments, the broken dreams and promises, the future that is forever lost, the future that will not be within your reach no matter how hard you try.
Not grieving is like building a house without a strong foundation; it's skipping the first process and eventually, you'll be haunted by your past.
You don't have to deal with the pain immediately. In fact, Henri Nouwen suggests in his book 'The Inner Voice of Love'
I started dealing with the pain of my parents' separation 20 years after it happened. I guess I wasn't ready to revisit this part of my life earlier. I didn't know how hurt I was; after all, my life turned out well. I did great in school and I've held my ground. But just because my life turned out well, it didn't mean that my parents' separation was ok.
Many people try to justify what happened in the past was good because eventually something good came out of it. But this is not an excuse to say that what happened was not all right. Every child has a right to a father and a mother who provide a loving and safe home. If the parents separated due to domestic violence, you can't grieve if you keep on telling yourself that it was for the best. As a child, you didn't deserve or need a violent household as much as you need separated parents. It couldn't be helped if you parents have to separate, but it wasn't the best situation. It was probably the best solution but it was not the best situation. Until you understand what you deserved - a loving family - you will not be able to grieve.
Never feel that you have no right to feel pain. But whatever you do, know that it is not your fault. You have nothing to grieve about yourself. It was the situation. Don't go into self-pity mode. Accept that there was nothing you could have done to keep your parents together. They did not get divorced or separated because of you - it was because of their limitations to maintain a family. Try to understand them and love them just the same.