This is so painful.
See, the thing is that Carol is completely and utterly wrong. Her actions up to this point have been wrong. Her decision here is wrong. Her being wrong got Rhodey killed. But she cannot accept that. She cannot have gotten Rhodey killed. Psychologically-speaking, she cannot handle the reality of his death and her role in it. The only way for her to deal with it is to be right, and so she cannot accept that she is wrong. In the face of all the evidence, in the knowledge that (as much of a pain in the ass as he is) Tony Stark has got the right of this particular ideological argument, she cannot face up to her role in Rhodey’s death. Her inability to deal is going to do a lot of damage, and when she finally does face up to what she’s done, she’s going to be devastated.
Or she’s going to continue on and become a full-blown supervillain.