First of all, dreams are usually unconscious reflections, which may be related to what you experienced during the day or to your subconscious mind. If your boyfriend makes you feel uncomfortable or stressed, he may show it in a bad way in your dreams.
Secondly, the occurrence of nightmares may be related to physiological factors. For example, poor sleep quality and incorrect sleeping posture may all lead to nightmares.
In addition, psychological factors are also one of the causes of nightmares. For example, you have experienced some things recently, such as lovelorn and unemployment. These mood swings may lead to similar scenes in your dreams.
In short, the feelings and experiences in dreams are often uncertain and cannot fully represent the situation in real life. If you often have nightmares, you can try to adjust your mentality and living habits and improve your sleep quality to relieve your symptoms. At the same time, you can also consult a doctor or psychological counselor for help.