Well, I think it's great you turn those feelings into aggression and communicate clear boundaries with people. Another way, which I do and don't like that I do, is I blame myself for over reacting, then push the feelings and act completely normal. That makes me feel more gross, leads me to passively trying to work around other people crossing boundaries, and makes the situation feel more abusive. Like I'm repeating some pattern from my screwed up childhood, where I'm always trying to hide my feelings, act normal above all, and seem to value other people's convenience and happiness more than my own.
I also feel like dealing with this is either not entirely an intellectual exercise, or that I don't have the intellectual ability to think my way out of it. All of my current problems feel like psychological issues, that I know can get severe, and solving them by 'thinking right' or 'thinking straight' or being analytical has never worked for me. It can help in some ways -- motivating me to try and fix this, and moving between different strategies when one doesn't work, seeking help here, and etc, but thinking alone hasn't been able to fix it.
There's this model of the mind where inside our brain is a little person, a homunculus, driving. That's an out dated model, but, anyways, the way I understand the idea is that the little man or homunculus is our top level thoughts: the top of our consciousness that's made out of sentences and paragraphs, the thinking part of our brain. And that's not supported by our modern understanding of how our consciousness works. I've read the analogy that it's more like dolphins swimming beneath the sea, and that top level is just whatever dolphin is breaking the surface at that moment. There's a lot more going on than a little man directing things, and ... I don't know, that somehow feels more apt to my breeds of crazy. I've learned I just don't have the ability to drown the dolphins with PTSD by having some little man inside me make all the right intellectual moves and constantly think exactly the best way. I tried that as a coping mechanism, as a child, and fortunately had the awareness that it was making me more crazy, and leading me down a kind of OCD rabbit hole that I knew would end up nowhere good.
That barely makes sense, and is probably wrong, but anyways it's kind of funny so I'll leave it there.