Colleague that "triggers" me

I got stuck a bit in a loop on this matter. (I know that is a thought).

I have a colleague, that even when I think of him, already dread working with him.

Thought Download: He will be so negative again. (What complaint is he going to come up next?). I wish he was more positive. I need to “protect” my emotional state before I meet him. I am not looking forward to work with him.

My model:

C: Colleague (meeting)
T: He will be so negative again.
F: Negative anticipation/dread
A: Avoiding meetings with the person, spinning in my head beforehand about the meeting with him, tense body, defence mode when meeting him
R: I am expecting negativity from him in advance/ I am negative towards him.

I have problems getting even to neutral here because my T “he is always coming up with something negative” feels very much like a C.

I would like some tips for getting to neutral or what to process.