Not dreams, but nightmares?

I have been having nightmares about a specific individual that I moved out of my life roughly two years ago.

Today I have tried to identify what is triggering them, as they have gotten more vivid and disturbing with each night and I seem to fall back into another nightmare of him. I have identitified none.

But now I am thinking about him and am running short on sleep esp restful. This is a stressful time in my life and I need to be on top of my game mentally.

How can I get a restful full nights sleep minus the ‘mares? Also could this mean I never recovered from the traumatic situation and need to take more steps to heal?