She is defining herself and her existence using critical theory, and so her perception of experiences is filtered through that world view. That will always create a "toxic" environment, not to mention just make a person miserable to be around.

Critical theory is useful for the purpose of study and quantification of different social bias, norms, tends, values, or whatever other social aspect you want to slice up. The problem is when people use those divisions to identify themselves. It forces people to identify with a certain group, when in reality the divisions are often not nearly as clear cut as they are defined. But over time people are pressured socially into moving closer to how their group is defined, and what may have once been a false dichotomy becomes a self fulfilling prophesy of sorts; where the social interactions are entirely defined by "my tribe" vs "their tribe". My tribe is all good, theirs is all bad, therefor we are justified in treating everybody in their tribe as less than human. Even is cases where there is very real injustice and evil taking place, allowing oneself to be defined by these groups does nothing to resolve the problem. It only serves to shore up divisions and conflict between groups, making it worse.

It is unfortunate that the admonition to "love your neighbour as yourself" is no longer held with high regard.