My mother in law controls manipulates my wife and I dont know how to change it?

My MIL has been acting crazy since day 1. For example, when we decided to get married my MIL didnt like the color we chose for the wedding becuase it would clash with her red hair so she pitched a tantrum and refused to come until we changed it. Anytime she doesnt get her way about something she pitches such a huge fit and makes my wife miserable. Right after we got married we moved about 2 1/2 hrs away and my MIL hated it. one day she took off of work and drove to my wifes office without telling us. When she got there she wanted my wife to take off for lunch but she had just gotten back from lunch and couldnt leave. My MIL started screaming and cursing. "I would never work for a F_cking place that would let me leave when I want to." It got so bad that the president of the company threatened to call the police. This has gone on for years and now my wife will give her mother her way just because she is afraid of the tantrum she will pitch. This has gotten to a point where it controls our lives. Now we have 2 children and I refuse to let me daughters see this as an acceptable relationship. On Father's Day 2 years ago we had to have the sheriffs dept come to my house. She literally through herself in the floor and cussed and screamed and kicked people all because my 2 year old was taking a nap and we should have been better prepared and had her awake when she got there. More recently, she has felt the need to bad mouth my wife and i in front of our children and has even told my wife that she needed to leave me and kick me out of the house because I am a troublemaker. All in front of our children. I will not under any circumstances accept this. I will not allow her around my children unsupervised. My wife recognizes that there is a problem but wont confront her mom or stand up to her becuase of the tantrum that her mother will throw. This is all very hard for me to deal with because I dont feel the need to stay stuck to my family. I dont need them around every holiday or make decisions regarding my family based on them. My thoughts are to move very far away and not give her our new information but I am not sure that will actually resolve this issue. Additionally, they have always treated my wife like trash. When we decided to get married they did not like it cause we were 20 years old. They cut her off completely. Took away the car they gave her when she was 16, cut off her phone and made things so much more difficult on us. They would stay at our apartment when they would visit and complain how bad our stuff was. No matter what my wife does it isnt good enough. My brother in law is nearly 7 years younger and no matter what he does its wonderful. He is 25 hasnt greaduated college (my wife has her masters) and parties and drinks all the time. He even has 2 DUI's When he turned 15 they bought him a new 4x4 truck. At 15 he stole the keys and was arrested for driving without a license, breaking city curfew and for littering. At 16 he wanted a new truck so he got it. at HS gaduation he wanted a $70k car and guess what he got it. He has no license but they still let him drive cause the cop was picking on him when he got the DUI and didnt really do anything wrong. When my wife graduated from college she jokingly asked her mom so what do I get for graduation and they replied we spent too much money on your brother we cant afford to give you anything. I really want to tell my MIL to F off but the other half of me feels like this is something that my wife needs to do or she will resent me for it. I do however refuse to let my daughters be treated this way. I see my mother in law trying to manipulate my 4 year old by making her feel guilty but so far it hasnt worked. We have worked very hard to raise our girls to be confident and strong willed. for example, my MIL showed up and we had company. My 4 year old was playing with her friend and my MIL was like you need to stop playing with him and come talk to me. when my 4 y/o said Im busy my MIL started crying and was going on about how you dont love me and you are so mean to granny. my 4y/o looks up with her head ****** and said you need to act like a big girl. I was so proud. I now have an opportunity to take a job that would be so great for my family. Its in a place my wife has always dreamed of living in. It is the perfect scenario except my wife doesnt want me to take the offer because her mother will be mad and throw a fit making her miserable. I am open to any suggestions. besides my MIL my wife and i have an amazing marriage. We are going on 12 years. I dare to say that 85% of the fights we have are over my mother in law. What do I do?