Welcome back here Hope45
I think it's great that in spite of all the difficulties you are also still able to see the positive qualities of your uBPD MIL. We describe several communication techniques on this site that might help you interact with your inlaws, such as
Validation. There are also some techniques specifically designed for communication with people with BPD that can help you speak your truth and assert yourself, while minimizing the chance of further conflict:
COMMUNICATION: S.E.T. techniqueCOMMUNICATION: D.E.A.R.M.A.N. techniqueThe acronym S.E.T. stands for Support, Empathy and Truth:
The S.E.T. communication pattern was developed by Jerold J. Kreisman, MD and Hal Straus for communication with a person with BPD (pwBPD). It consists of a 3 step sequence where first Support is signaled, then Empathy is demonstrated and in a third step Truth is offered.
The acronym D.E.A.R.M.A.N. stands for Describe, Express, Assert, Reinforce, Mindfully (keep your focus), Apear (confident) and Negotiate:
D.E.A.R.M.A.N. is used when you have an objective, you want something specific, such as to get more sleep, to have help with the chores, to affect a change or to say NO to a request. You want the other person to come away feeling good about you and not full of resentment. This preserves the relationship. You also want to protect or even enhance your self respect.
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The key to acquire the skill for DEARMAN lies NOT in following the letters. It lies in learning the underlying skills and practicing them well enough to then being able to steer a conversation through DEARMAN. When looking at DEARMAN it is clear that we are to express needs for change.
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DEARMAN is valuable skill that at its very core boils down to:
We have a right to ask for change - the other side may or may not agree, that is fine too.
When owning up to our requests, staying respectful and focused on what we want we improve our chances for affecting change.
Perhaps applying these techniques can improve the relationship you have with your inlaws.
Dealing with someone with BPD can indeed take quite a toll on you as you unfortunately have also experienced yourself. Do you feel like you are able to take proper care of your own well-being and are able to at least now and then re-charge your batteries?