The symptoms of severe stress, sleep issues, memories of that person and associated abusive behaviour needs evaluation. This can be a post trauma related stress and should be immediately addressed. The stress and sleep part can be handled quickly by medications and for the memories part/ things you keep remembering you need long term psychotherapy. Psychotherapy is kind of a counselling given by trained person.
Next Steps
Immediately reach out to near by psychiatrist and handle the stress and sleep first
Health Tips
Try relaxing in your own way, may be an exercise, a walk or a basic yoga, only if you are confident to do.