Don't take onto yourself the other persons problems, the things they do or say that upset you. All that is yours is reaction to it...
It doesn't really make it any easier at the time, but after try to step back, calm down and process what you are really thinking and feeling...
I can appreciate your frustration and anger after so much effort to be undermined by this. I think it is totally understandable
I really appreciate the huge effort, emotion and guts it takes to try and understand the way you work... its gut wrenching at times.
Last time I had a horrible violent reaction to a trigger (a couple of weeks ago) the really horrible depression went almost as quickly as it came, and by now I feel normal... Here's hoping the same goes for you