Hi missmoose
Sorry to hear about the problems your dad is causing in your family.
BPD is quite a challenging disorder indeed. The fact that your dad seems unable or unwilling to acknowledge any of his issues, unfortunately only complicates things further.
To help you interact with him, I encourage you to look at some of the resources on this site. Specifically the specialized communication techniques, I have selected two for you:
S.E.T.: Support, Empathy, TruthD.E.A.R.M.A.N.: Describe, Express, Assert, Reinforce, Stay Mindful, Appear Confident, NegotiateAre you familiar with these techniques? They can help reduce the likelihood of (further) conflict while maximizing the likelihood of getting through to the other person.
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.
Few tools are easier to learn as S.E.T. and are as effective in getting across to a pwBPD. Few tools are as universal in everyday life with anyone. It is sort of an walking-on-eggshell antidote.
After wandering in the FOG (fear, obligation, guilt) for a longer time we have lost the natural instincts and ability to ask for something. Fear is controlling our thinking. Our family-member/child/friend/partner is super sensitive and tends to over-react. We get ever more careful, stopping to ask for things needed in our or our relationship's interest. Resentment breeds. Resentment is sensed. Communication grinds to a halt. How do we get back to normal? A big step is start asking again for what is needed and this is where D.E.A.R.M.A.N can help us.
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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.
Take care