I don't know if it is the painkillers, Spitfire. I have used them in the past for serious back and leg problems which I was able to entrain my body out of with therapy. They did not affect my dreams.
However, I do believe that traumatic circumstances can resurface in our dreams as our mind begins to process more fully what has happened to us. I suppose it is a way of reliving and re-understanding our relationship to the pain we have experienced.
So, yes, it may be an opportunity for you to examine yourself within the dreams, notice the roles you are playing, how you are reacting, and to notice if you are on a "healing" path, which to me means becoming stronger and able to control the circumstances, initially, and then calmer and able to transform the experiences at a later stage.
This is my limited understanding of the nature of such dreams, if they are personal.
If they are impersonal, and you feel no emotion from them, just images you remember which are disturbing....then this also could be the result of trauma, I believe. I would suggest surrounding yourself in your daily life with very positive images. Look at them daily. This will seep into your subconscious mind and help you. Feed your mind also with words and books which are healing.
Just a suggestion.
much love, blink