Accused of having no brain…? I am at such a loss. Do you really think I have resorted to ad hominems? If so, I apologize, but I’ll be honest: I don’t see it.

There is a causal relationship between LW’s gf bringing him lunch and his coworkers teasing him. There must be language that describes that relationship while also acknowledging that the coworkers, not the gf, are the bad actors here. I don’t know what looks like for you, but to me the letter provides a short and factual description of the situation. The request that the gf resolve the problem does not, in my mind, imply blame.