As a writer, have you noticed how easy it is to recall fun slices of your life and write about them without any problem? It would seem that the replay in your mind is so clear that if you can slip a video recorder in your brain, the playback could be considered as high definition.
On the contrary, unhappy incidents, especially violent ones, are difficult to remember in detail, our brains seem to block parts or even a whole chunk to protect our present sanity. And to put them in writing is a torture, the reenactment in our minds causing more harm than good.
Experience is the best teacher, so they say. Good ones could motivate others, even entertain. Bad moments ask for explanations, even pity, or worse indifference.
I like to write about happy events. Unfortunately, in reality, I also need to relate the way things are: often bad.
But, the good side will always prevail in the end. I am recording them in my brain.