How many of you hold on toe grudges or are holding on to one from your past? How do you deal with them and why?

There have been people, friends, family, ex who have "done me wrong" and I assume I have done to the same to others some point in my life. When I was younger 20s/30s I held on the the grudges and relived them in my mind, always thinking what I could have said or would say when I saw them. Then I realized everytime I brought out the grudge it was only hurting me and taking my time away from living now. I since have tried to let go of my grudges from my childhood and adult live.