my husband is like this too. when I complaint about the maid to him, he would either defend her or ignore me. This made me even more angry. But after I really talked with him, I understand now, he doesn't want to have trouble and changes at home! He is feeling comfortable and the children are happy, why change the maid just because you are disrepected?
We have to help ourselves.
When my maid did something disrepectful, I talked to her immediately, not scolding her but just told her what I wanted her to do.
e.g. When she didn't greet me at once after I went back home, I talked to her immediately and asked her to greet me everytime. And I told her that it was impolite not to do so.
e.g. For a while, she would "remind" me to tell her what to prepare for dinner, even when I was busy. And I didn't like this, so I just told her that she doesn't need to "remind" me in the future.
Luckily for us, she does improve after being told clearly what she needs to do. So I can still keep her.
I think it is not good to keep the disrespectful maid after really talking to her. The children would learn from her that you can get away by treating others well but not mummy. This is a bad thing, and it is hard to discipline the children if they learn this.