Did you have the romance conversation with her and let her down easily? Because as far as I can tell, the game seems to set that as "broke up with Xoti" instead of "did not start relationship with Xoti." I had that on two playthroughs, one before any DLC came out, and my current playthrough that I started a week ago.
I don't have confirmation that this is the cause, but she starts responding like that immediately after letting her down easily, and it's really weird.