I have always had this problem and it's the main reason why I am quiet, have social phobia, and prefer to text people instead, but even then, trying to write a sentence in the correct order without it being an illogical, over-emotional mess can be embarrassingly challenging. The worst part for me is not knowing how to respond perfectly to the person I am talking to without having to choose the many answers my brain has annoyingly conjured. When this happens, I have to hyperfocus on what was said by the other person in order to produce a pleasing and appropriate response, but it's so tiring, so I usually have to make excuses in order to give myself more time to think clearly.

Also, the inability to communicate in real time with people is why I’m sometimes perceived as slow or stupid by other people, and it’s why I think I’m slow and stupid every single day. This is one thing I loathe about myself and something I wish I knew how to improve on.