The dream of killing people generally reflects the individual's need to vent their depressed emotions, which you should know. Here, your dream embodies two characteristics. First, your dreams are relatively fixed, indicating that you have relatively certain demands; Second, it is irregular and continuous, and there is no fixed pressure source, which shows that it is a deeply repressed emotion. I agree with upstairs that this may be related to early traumatic memory. However, the inference of "castration complex" seems arbitrary, at least the argument is insufficient.
Generally speaking, "decapitation" is a situation you hate but have to face, which corresponds to your past and reality. Actually, it fits your description. The memory of parents' divorce is partially forgotten protectively, but once the consciousness of "separation from relatives" is awakened in a different place, it will be forced to bring out unpleasant latent emotions in the dream, so the subconscious will choose to finish and end this emotion by beheading. Here, because you have to admit that "separation" is a fact and difficult to face, you will eventually choose this way to "settle"-"it should not be separated, but it must be separated".
In the dream, I'm not sure what ideas or ideas those characters represent, but I guess it has something to do with your mood. You have a strong self-regulation ability, so you keep trying to pull away from your dreams, so you set a "deadline" in your dreams and finally managed to control your emotions, which is worth celebrating. However, even if there are similar dreams in the future, I hope you can treat them with the same detachment, because some early memories are difficult to eradicate and can be diluted, so you should take them lightly.
Usually, the best way to solve this kind of problem is hypnosis, but it may not be necessary to look at your current situation. Perhaps a complex has been released through a long-lasting dream, so I also hope that you can get out of the shadow of the past more thoroughly. Wish you all the best.