Why is my friend acting like this?

My friend and I were really close until she started dating her best friend. They had a nasty break up until they got back together. Every single text (which was like 80+ a day) was about him. She would always ask me for advice and I tried my best to give it to her. One day I couldn't take talking about her bf that much and I told her how I felt. She blew up at me and I just stopped texting her. She apologized and we were cool. Then they broke up again and she was really happy about it. Then she's telling me she loves him and blah blah blah. Since the break up she asks me for advice, I say something, and she blows up at me. I really have no clue what to say. She always apoplogizes but then she gets mad at me again. It feels like the whole world revolves around her and when she doesn't get what she wants, she blows up. She has even admitted she hates the word no. I try to be a good friend but I just don;t know what to do anymore. It seems like it's a give and take friendship, she does the taking and I do the giving. She can be a real b***h sometimes and I can't handle it. She is so manipulative. What should I do?