I think it's impossible to answer the question unless you have some sort of overall approach to dream interpretation. What you're asking about can't really be asked a general question, you'd have to look at each dream, it's symbolism, it's nuances, what it's representing to you and so on.
When you ask what does it mean, the question needs to be taking one dream at a time and looking at what that means, ideally with a therapist trained in dream interpretation or at least from your own reading/learning about dream interpretation.
A dream about an aspect of trauma might be due to subconscious/somatic processing and working through what happened, it might be trying to bring something to your conscious attention to work on, it might be using what happened to symbolise something (eg helplessness) to mirror to you that you're manifesting helplessness in a current, completely different situation.... it could be many things.
Sorry, but I don't think there's any simple answer for your question. What I would say is that I no longer believe anything in dreams is randomly generated by the mind. I used to think this. I imagined it like my subconscious flicking through what happened today, yesterday, 10 years ago, 17 years ago and than randomly stopping at something and putting that in my dream. The question is, what does that seeming nonsense/random thing have to say to me now?
Now - having worked with dreams for years - I see them as astonishingly sophisticated and attuned. It's not that my subconscious randomly picked something that happened 17 years ago, but that it very carefully selected something that happened 17 years ago because that's the perfect thing that will reflect to me something I need to think about today.