We *had* the exact same probs with MIL till it all just blew up one day and now we only see them for Christmas which is absolute BLISS .

My MIL and SIL used to always have her their say on what we should be doing with DD. Like use cloth nappies, dont B/F, get her used to the pram, dont let her get to clingy to you blah blah blah. I used to grit my teeth everytime something was said until it got to the point where i thought 'no way, this is OUR daughter so enough'. I started biting back HARD. At the time DH didnt really do anything because its was his family and didnt want to upset them but he soon realised that he HIS family to protect and it was time to start saying something.
Of course they didnt listen and thought we were in the wrong, very typical of his whole family. DH has a cousin that is having the exact same probs with his parents now.

I think when there is a problem with your family then YOU should say something but if its a problem with his family then HE should say something. If all else fails and they still dont listen then do what i did and write everything that you need to get off your chest then ring MIL and say your peace. It worked for us. They no longer drop in when they feel like it anymore, they dont ring, they stay right away.
I was pretty blunt with what i said to her and to this day DH hasnt asked me what i said. He is confident that i said all the needed to be said because they wouldnt listen to him. He said if they dont listen still from my talking to her then we will severe ALL contact with them.

He has had enough of the majority of his family. He cant stand his mother or sister anymore. He would like a relationship with his father but knows thats not likely to happen cause his married to his stupid mother.

Look after you and your family, screw the rest i say. If they cant respect what YOU want for YOUR daughter then she should be told not to come around anymore and to ring first to make sure its ok. She should be ringing first anyway before visiting, thats just rude to just turn up like that. Tell DH how you feel and tell him your uncomfortable with her just dropping in. He wont understand to begin with because he has been raised that way so he wont see it as being a problem but you have to make him understand that that is not how your were raised and you dont like it.
Stand you ground and be strong, she has NO RIGHTS over DD and she should be told this. And bugger the staying over part, if your not comfortable with it then dont do it.
My MIL bought all this stuff like portable cot, car seat, basinett, bedding etc because she ASSUMED DD would be staying there. No Way!, i told her to get rid of it all because she wont be useing it with my kids. Lol.

Be strong. you have to be, otherwise she will take over. Stop her from taking over DD when she is there to. She doesnt have the right.