I think that your ex gf hurt your feelings. Perhaps she was the first to say that you didn't treat her well while you were together.

People say all sorts of mean things during arguments. Sometimes, we seriously mean the words that we say. Often though, we don't. We just become a little hot-headed and say things that we don't really mean. I would guess that's what happened between the two of you. Perhaps you made a remark that hurt her feelings as well??

Something worth thinking about from that angle. It sounds as though her words hit you hard because now you're over-analyzing everything that you say and do. Maybe you should call your ex, apologize for ___, and let it go. Or, maybe she was just being real mean to you and an apology to her wouldn't help. You could ask your friends if you've seemed different lately. In a good or bad way? Try to work through your past mistakes so you can let go of this pain and confusion.