Hi mindfulgraditude,
I want to join
Struggles and welcome you to the BPD Family
You are not over reacting, you
are experiencing the things you are experiencing, how do I know because I have too. The person with BPD (pwBPD) in my life is my significant other's (SO's) undiagnosed BPD ex-wife (uBPDxw).
It's amazing how subtle some of this stuff can be... .something is just off, you feel it, you know it, but it can be hard to explain to someone else that hasn't experienced it. Yes, it can also be blatant in your face drama too. Because others (your friends/family) haven't experienced mental illness they can unknowingly invalidate your feelings and experience... .she didn't mean it you should forgive and forget... .just apologize to end the conflict and move on... .she's doing the best she can, it's not her fault... .
I will say again you are not over reacting you are starting to set boundaries... .not tolerating her bad behavior, protecting your children from the dysfunctional dynamic she along with your enabling FIL are creating, stepping back from the drama/conflict etc. All healthy choices in my opinion.
You as the outsider (someone who married in to this family) will be better able to see what is going on. Your husband has been raised in the dysfunction and may have a harder time, his receiving therapy is excellent it will help him step out of what we call FOG (Fear, Obligation, Guilt) that is often used by someone with BPD to get what they want. Do you see your MIL using FOG (or Emotional Blackmail) to get what she wants?
More on FOG... .
https://bpdfamily.com/message_board/index.php?topic=82926.0Our latest episode/explosion occurred last August - my Mother In Law began a massive campaign and aggression against me (I won’t go into details, but it’s been horrible and totally crazy making). After this last episode, I’ve asked for “some time and space to think about my response” and have essentially been no contact, which has resulted in her launching massive bombings on me and my husband.
I also wanted to mention an Extinction Burst... .
Extinction BurstThe phenomenon of behaviour temporarily getting worse, not better when the reinforcement stops.
https://bpdfamily.com/message_board/index.php?topic=85479.0Essentially an Extinction Burst can happen when you don't do what you have always done. You have set a boundary... .I want to take some time away from this relationship and the drama (again a healthy choice!

) You have not acted like you always have which, if you are like most of us, was to back down and do what she wants you to do. So she has escalated trying to get you to do what you've always done and back down.
Look at it like a little kid in the Grocery Store... .
A little kid asks mom for candy, mom says no... .kid pouts. Little kid asks mom again for some candy, mom says no... .kid whines. Little kid asks mom again for some candy, mom says no... .kid has a full on melt down screaming tantrum. (Which is what your MIL is doing with her "massive bombings"
What happens if mom in my story gives in and gets the candy? That little kid has just learned that having a screaming tantrum will get them what they want. What happens if mom doesn't give in? The kid learns that no means no and he gives up. This may take some time (and not be fun) and this does not mean that the kid/your MIL won't periodically test the boundary again to see if she can boundary bust (or get the candy). The key is to enforce your boundary.
So as the description above says when setting a boundary with your MIL things can get worse before they get better. Hang in there and do the right thing for yourself and your immediate family.
More on Boundaries... .
https://bpdfamily.com/message_board/index.php?topic=61684.0https://bpdfamily.com/message_board/index.php?topic=167368.0https://bpdfamily.com/message_board/index.php?topic=206736.0Some books you might want to checkout... .
Overcoming Borderline Personality Disorder: A Family Guide for Healing and Changeby Valerie Porr
Stop Walking on Eggshells: Taking Your Life Back When Someone You Care About Has Borderline Personality Disorder by Paul Mason MS, Randi Kreger
Understanding the Borderline Mother: Helping Her Children Transcend the Intense, Unpredictable, and Volatile Relationship by Christine Ann Lawson
I also wanted to suggest if your husband would be interested that he join our group too. My SO and I are both members here and it has really helped us gain a good understanding of BPD, get support and understanding, suggestions for Tools and resources that can be helpful, speak the same language and work better as a team when it comes to his ex.
Wow, I've been very chatty

I think I'll let someone else get a word in!
Take Care,
Panda39