Constant poor behaviour, lack of boundaries (especially physical), rudeness, back chat, disobedience. I try very hard not to get angry, to be firm and clear, but she just doesn't learn. An example. We have 3 chickens. She loves to play with them. Has been told a thousand million times that she can't pick them up. And what does she do. Picks them up. Every. Single. Time. Sometimes even as I am actually telling her not to. We have had a horrible afternoon, and now evening. She was out of bed, wanted some toy: I said "no" it's bedtime, now escalated to full-scale kicking, screaming tantrum, including throwing stuff at me. I just want to cry, I do not know what to do with her.
I have tried the talking to her when she is calm approach - she runs away, or doesn't listen, changes the subject. Never accepts that she is in the wrong.
I don't expect you to have the answers - just ranting really.