I can't believe you fired an assistant that had been with you for three years because she brought you a co-listing that would have made you a commission. Even if you thought it was a bad idea, you could have just explained to her that she needed to walk away. You could have worked out with her the boundaries of your new arrangement. Maybe it was a bad decision on her part to accept it, but it was a listing and she thought you would be happy. Then you have the temerity not to pay her for past work owed? Someone who you regarded as a sister? Then she is not even allowed to ask for a recommendation? I can see why she got so emotional and behaved that way, even if it was unwise.