Nice to meet you. @Shaz51 is right, there's a great bunch of people on here.
I can't recall of many people with parent who have BPD. But there are a few people on here who are parents or partners. You may want to check out this thread by @Allig. Her daughter has been diagnosed with BPD. She may be able to give you some advice around how to respond to your mum's behaviour. In that thread @Makettle also talks about some of the hardships of providing support for their son.
We also had a special event, a Topic Tuesday, on Debunking the myths of BPD, which you might find useful too.
One service that you might also find helpful is spectrum. They're based in VIC. Not sure where you are, but they can be a good resource to get more information.
Hope this helps a bit.
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