How do I deal with my Mother in Laws antics?

My mother in law can be nice but most of the time she is calculating and manipulative. I have kissed her *ss for 6 years - this year I have decided no more. During midterms she showed up at our house unexpectedly to stay for a four days and surprise us with my stepson. I love family and her surprise visit wasn't what made me angry it was that my in laws trashed my house, their dogs pooped all over our yard and when I asked my MIL to watch the grand kids for a couple of minutes while I ran to the store she was actually offended. My parents call us once a week to ask if they can have the grand kids! I had to stay up until 5am to get my papers written and I also had to do damage control on my home because they didn't lift a finger. (Not elderly - in their 50's). Also she told my husband not to look into moving for a better job so that we could have a home because she wanted to buy a property in our town and rent to own to us. I didn't like that idea much but she sucked him in and then called us after better opportunities where past to tell us she changed her mind but that we had better not move because she may want to live here. We said - No way! We have to provide the best life for our family we can right now. She was mad again. I forgave her and moved on but she has some imaginary hurt all of the time so I kind of avoid the hr long Skype conferences she demands once a week. I pop in and say hello then pop off to tend to housework, home work or kids. She is getting mad about that now. She is bringing my stepson up next week and we are planning a birthday party for him- he is 10 and we thought it would be fun to take him to the drive in since we live in a small town and when he grows up they will most likely be gone. She flat told my husband that if we chose to celebrate his birthday in that way they wouldn't come. That pissed us both off because she shouldn't be micromanaging our boys birthday party. I relented and said that what ever she came up with would be fun and perfect for his birthday. I am really mad and I think something needs to change- so what do I do next time she pulls this control freak behavior?