I really want to explore something with the help of the very wise posters here. I don't post much and much of what I do post is pretty negative stuff about my marriage. I read here constantly and it has helped me and my marriage so much (even if I don't post the triumphant stuff). I also have read and read the books and my H and I have done a chunk of the home study course; we will start back up in the fall. In the mean-time we do get our 15+ hours of UA time and do a pretty good job of using POJA etc. There has been no infidelity.
I'll dive right in and put the background and long-winded explanations at the end for those who would rather skip them

My MIL is controlling, bullying and needs an enormous amount of admiration. Her way is the right way and she is disrespectful of people who do or think differently than she does. She disrespects me and our parenting decisions constantly. This is done through dismissive comments, eye-rolling etc. She is constantly pointing out things she thinks are unsafe (making me feel like I am not a good and cautious wife and mom, almost without exception my choices are NOT unsafe). She believes that only her nuclear family are worthy and puts down and treats poorly my Husband's older half-brothers as well as my family. We had been doing holidays and birthdays with my family and DH's family together but after the last we will no longer be doing that. She is openly hostile, mean and vicious toward my mom and bad mouths my mom TO ME constantly. She complains to my H that I am nicer to my mom than I am to her, that I compliment my mom more and spend more time with my mom etc. She complains to my husband if my friends seem closer to my mom than they are to her (they are). She makes snide comments about my friends etc. Now, I have to emphasize that this is how she operates generally. It is not reserved for me and my friends and family. She is passive aggressive and controlling. ILs are extremely wealthy. Our family decided to rent a vacation home for the summer and they rented one within walking distance. They have made it clear that we have "no choice" and they will always live close to us. We bought a fixer upper 25 minutes away from our current home and within 10 days they had an offer on a house less than a mile away. This bummed me out because I would have enjoyed thinking and dreaming about our new neighborhood etc. with my husband for a little while before having to talk to my MIL about OUR new neighborhood. The list really does go on. She is warm, generous, outgoing and funny. People that don't know her very well think she is WONDERFUL!
What I have done and want to do to improve the situations:
-We will no longer do holidays and birthdays with both families. My DH told her this after a disastrous Mother's Day this past May when I announced my pregnancy and she was overtly rude and mean to my mom.
-I finally was able to POJA with DH that my sister could baby sit our son. Previously he was only comfortable with my mom, his mom or his mom's assistant babysitting and since MIL makes snide, aggressive, disrespectful or controlling comments almost every time I see her having my sister babysit for more of our UA time has been a huge improvement!
-MIL's assistant no longer babysits for us (this was fraught with problems including MIL telling her to go against my wishes and using her for info etc.)
-I have been better about letting my H know when I am not enthusiastic about hanging out with ILs while not complaining about them or being negative about them and it has been working well!
*I really need help with talking to her about her mean, hurtful and controlling comments as they come up and working through conversations about the new way of doing holidays*
It is going to come up that I do not want to be with her and my mom in the same room as much as humanly possible. Even when she is polite to my mom she is nitpicking and will criticize everything my mom does and she will express these thoughts to me or my husband so I always know how she feels. It causes me enormous stress and I want to be able to calmly explain that I can't handle the dynamic. How do I do that? It's the conversations that I am struggling to figure out.
What EXACTLY do I say when she makes a little snide comment or disrespects my family or my parenting ideas or me?
I am losing sleep over this!!
And yes, I want exact words. Words matter. Saying "how would you feel about blahblahblah" during POJA is like magic. I need more tried-and-true magic phrases in my life...
She is defensive and vicious and will not take a "that hurts my feelings" or "please don't say negative things about my mom" without lashing back in a big way. It has been MY desire to avoid this lashing out (conflict avoidance!!) that has caused much of the mess we are in today. I am responsible for how far this has gone and how damaged our relationship is. Instead of calmly saying something I say nothing but withhold the love, friendship, affection and admiration she so desperately wants from me. I "get her back" with comments of my own etc. I have no friends, zero, that make snide or passive aggressive comments. I am not quick-witted and I have trouble doing anything in the moment but I feel hurt and stew about it later. The few times I have stood up to her effectively have been INSANE and resulted in her saying horrible brutal things to me and when I calmly stand my ground and leave/go home her pretty much saying "I don't know why I said that" It hasn't made things better and I know that MIL genuinely feels like she walks on eggshells around me. I respond to only a fraction of her comments and that is still more than anyone else stands up to her...she often has NO IDEA what went wrong when I avoid her and distance myself. At the very least I would like to give her the opportunity to understand. I do know she may not be capable or willing to understand...but my conflict avoidance is not entirely fair to her either.
Any words of wisdom on how to deal with a dynamic like this?
Why I am posting about this here:
The biggest thing I have learned reading here constantly and reading the often broken-record responses from the vets here is: I can only control myself. I can control my emotions, I can draw boundaries, I can choose not to fight, I can be honest about what bothers me and I can be proactive about getting my needs met etc. My relationship with my MIL does have an enormous effect on my marriage but is not strictly a Marriage 101 issue.
The way I understand it is: in a true MB marriage I could decide, for no good reason, that I wanted to sever ties with my MIL and my husband (if he wants to have a successful marriage) would need to accept and support that. We could also POJA our level of involvement with his parents etc. Well, I feel decently good about how we are dealing with MIL within our marriage. Not great, but good. I think that if I can do a better job of dealing with MIL our POJA etc. will improve dramatically.
I am going to attempt to dramatically change the way I deal with MIL and I would love your help, if you are willing. For the last 10 years she has caused me great distress and pain. I have spoken to a therapist about it and confided in trusted friends who are willing and able to tell me when I am in the wrong. But no one can give me advice on how to deal with her other than avoid her. My Dear Husband has no trouble telling my what I do wrong in my relationship with MIL. It is one of the only things he criticizes me for. To his credit, I sometimes behave badly in my relationship with MIL, which is very out of character for me. The second someone is aggressive or passive aggressive with me or bullies me etc. I end or limit my contact with them. I do not thrive on drama. That just isn't as easy with family. My father is mentally ill and I maintain my relationship with him by having clear and enforced boundaries. Other than that I don't have much practice dealing with very difficult people. I have had a tough time in my marriage, but my H isn't difficult, we just did not know at all how to have a good marriage!
The reasons I want to attempt to have a better relationship with my MIL are:
-she supports our marriage and has an MB marriage
-she desperately wants to have a closer relationship with me
-my DH works closely with his father in the family business
-DH's family is unusually close, it is not a typical family dynamic (can explain more later)
-I want to use some of what I learned here to attempt to improve my relationship with MIL
-I have behaved badly and if I have to tell my husband I want to sever ties with his family I want to do it from a place of having done all I could and I actually gave his mom a chance and guidance as to how treat me well. (a la, stating needs and working on a marriage before calling it quits or having an affair)
-I need to hone all the skills I need to have a good marriage. I find that I control my anger with my H best if I control it everywhere, always. I do better at not avoiding conflict with my H if I get into the habit of not avoiding conflict, etc.