My suggestion is, take her at her word. If she wants to move on, let her move on. Ignore her comments about you being "toxic" if they bother you; people give all kinds of reasons when all they are really saying is, it's over for me. If it's over for her, it's over. You can't have a relationship by yourself.
I have a feeling there is more to her story than you know about. Do you have contact with her after she broke up with you?