If you feel injured, you start thinking about it a lot, and thinking about it a lot, often makes the injury feel even worse. This is true also for wounds you have, they might be physical or emotional. If you think about all those inner wounds all the time, they will get so much attention, that they shout even louder at you. But, if you try to hide them away, if you try to focus on other things, then this will often help you see other things, and it will heal the injury itself.
Source: Bing Designer
Of course, if you would share this with a psychologist, they wouldn't agree, and that is entirely true, because if you have wounds on the inside, just hiding them and trying to push them away often just creates an even bigger wound on the inside and it will cause way more harm than actually opening up, understanding, and let that wound heal in a natural way. So, opening up about incidents and actually looking closely at them is often a solution as well.
But, then you have those carrying wounds around... a bad boss, a negligent sibling, or a stupid football coach who said something bad... and you just live in the past, instead of moving on and being in the present. I think the wisdom of Marcus Aurelius can be good for many of us!