Suprabhatham.
The principle of karma is such a healthy thing to save the mind. It's such a good vaccination for the mind. When you say karma, then you are able to let go and move on, otherwise you brood over whatever has happened in the past,and you try to link things with some cause.
If you look back, whatever you thought as cause is also an effect, it is not the cause. Every time you fix something as the cause of an effect, you have erred. You have seen that it is not true; it has not stood the test of time. No cause has stood the test of time because every cause is an effect. This is the spiritual way. When you think in this direction and go deeper to the ultimate cause, you find that there is only one thing that is the cause of the entire existence. With this one realization, your peace can never be taken away by anybody or any incident on the planet; nothing can move you if you know the cause!
That is why there is a beautiful verse in Sanskrit,"Tasmai nama parama karana karanaya", Shiva, you are the cause of all causes, the grand time that is beyond time, otherwise we keep going round in this cycle of karma.