Hi Sokash1119,
I’m sorry you’re having to go through all this. The behaviour you mention does all sound very BPD, so my guess would be that behaviour would still remain in some form, even if the drug dependency stopped. But you have understandably pulled away from what sounds like unacceptable behaviour. So my first question is do you need to do or say any more ? A BPD will always trying and draw us into the conflict, because that’s where they can best manipulate. So don’t get drawn in, which means think carefully if there is a need to respond at all.
If you do respond, do it on your terms, so avoid knee jerk responses. Write the letter/ e-mail when you’re angry by all means, but then when you’ve cooled down decided if you need to send it at all. Never forget, your BPD is deliberately being provocative, as they want to draw you back in (normally by drawing you back into an argument). If you do wish to send it, I normally find it best to pull out all the emotional and angry stuff I wrote when emotional and angry, before sending. This is because a BPD is the master of emotional arguments, they fog up when we present evidenced, scientific argument. So you can at least cleans the message.
Also here is one technique to communicate with someone with BPD, whilst closing down their options to escalate the drama:
S.E.T.
https://bpdfamily.com/parenting/04.htm