A very good article! There is a saying that goes something like this:
When you harbour hatred it is like taking poison and expecting the other person to die.

By not letting things go, you only hurt yourself. The other person is likely oblivious to your suffering or just plain doesn't care.

What I found very helpful was to try to understand why the person who hurt you did what they did. Often it is for reasons of self-preservation (or at least they BELIEVE they are protecting themselves or their ego). When you understand why someone might do these things, I find it easier to accept and forget about it. There is no reason to condone what they did, but just acceptance is good enough to set yourself free of the shackles that otherwise torment you. Finding inner peace actually takes some effort, but it sure is worth it!

Your mind is actually very powerful and will affect your physical health! In order to be physically healthy, you need to keep your mind healthy too.