Why don't I ever learn?

My 50-yr old ED called me 8/13, after years of snubbing me only to say her boyfriend had left her, and he and his mother had taken their 10-yr old daughter, by force. I eventually learned it wasn't that simple, the police told me she gave me a self-serving verrsion of what really happened (including leaving out her being arrested for assault), but I continued to try to help her. All the next 5 months I felt so grateful she was at least talking to me again, and I did everything I could to give her support and practical advice about how to get custody. Before long, I noticed her "suffering" was really much more about the woman he left her for (my ED kept sending me FB pics of her and them together) rather than the missing the daughter. I spent dozens of emails & phone calls trying to help her, each requiring hours of research re custody on my part. Each time, we erupted in another battle about her refusing to listen to my advice and her refusal to put custody over her pride and ego about being left. (That can wait--her custody hearing is in May.) I asked her for her court dates and the ones she gave me in May did NOT agree with the court's online docket, so those weren't even the truth. It got worse and worse, he had gotten a TRO against her and she flagrantly violated it at least twice, again with violence. I protested, and her last words to me were that she and her boyfriend had agreed at least on one thing: that I was "a piece of garbage." 
I have since blocked her email and do not plan to take any phone calls. I am done. I don't even feel guilty anymore. Those were the magic words!