My girlfriend changed her signature and said that you have your principles and I have my choices.
Maybe you made her do something, and she didn't like it, so you were very unhappy. Maybe two people had a fight. Then she will think that you have your principles, and she will do whatever you ask her to do, but she doesn't like it. She is a human being, and has her own ideas and choices. Personally, I think so ... because I don't know your cause and effect, I can only guess like this.