Hello Everyone,
I am very happy to have found this board. I want to introduce myself and my situation... .and I'll try to keep it to a small novel size.

I am a 44 year old female who is married to a great guy (6 years) with 2 step-children (not really children, both in their 20's). Anyway, I am sure that my mother has BPD. There is not one of the hallmarks that she does not possess.
I finally felt inspired to share my story with others because my family and I are desperate. She has gone off the rails - so to speak - in the last few weeks and we are at our wits end. When I say we, I mean my husband and I, my brother and his wife and kids and also my dad.
A little history - my parents were married for 22 years when they divorced back in '92 or '93. Fast forward to 2014 and my parents reunite and last year they got remarried after being apart for all of that time. Things were wonderful, great... .as long as she wasn't having an episode, and miraculously she didn't have one of her episodes for the entire time her and my dad were engaged (1.5 years).
I am 4 years older than my brother and I endured the majority of my mothers abuse during our childhood. My brother was "the golden child" and he could do no wrong. I fought with my mother, bad, bad fights, almost daily from the time I was 12 until, forever it seems. I have been in therapy myself for the last 4 years, trying to get past my childhood and make peace with it. All through my 20's and a majority of my 30's I drank, did drugs, anything to try and self medicate, just to get through things. Another miracle is that I made it out of that behavior alive. I now have a good job and a great life... .other than dealing with my BPD mom. Anything used to set her off... .if I used too much hairspray, if I wore a certain outfit, did my makeup a certain way, nothing was outrageous enough for her to make a huge deal out of. For many years I thought it was me, that I was doing something wrong.
Current day: my brother and his wife are expecting their third child. The baby will be born this week. My mother has ALWAYS felt like his wife "took" my brother away from her. She goes long periods of time where she is "normal" and she is nice, helpful, babysits, and is a pleasure to be around. BUT... .and this is huge... .always in the back of her mind she is thinking that my SIL is plotting against her, to take away her son. We all know this is ridiculous, and no amount of reassuring her otherwise works. After reading all about BPD, I now understand why. She absolutely cannot be reasoned with during her episodes. She has become rude and condescending and she is starting to exhibit truly scary behavior.
Yesterday, my SIL called upon my dad to pick up one of my nieces from school because she wasn't feeling well. My SIL is just about fed up for good with my mother, so she is not feeling comfortable calling her now, so she called my dad. Well, this just completely set her off. She proceeded to get drunk (she is NOT a drinker, my dad is a recovering alcoholic). While drunk, she said just horrible, hateful things to my dad... .nothing I haven't heard all my life, but she told him she wished he was dead that way my brother would only call her. She called me and begged me to forgive her for being a horrible mother. She wished she was dead, and on and on and on until she finally passed out.
Forward to today: I spoke with my dad and he said my mom woke up and didn't say much. That was to be expected. Every time she has her "episodes" (and I use that term, because I don't know how else to call it), she is quiet for a bit, then she tries to apologize, but never acknowledging all of the hurt she caused during the fight/altercation, etc. At this point I decided to get involved (much to the contrary of everything I've learned in therapy in order to protect myself). I called my mother and pretty much gave her an ultimatum... .that if she doesn't seek therapy and try to get help, then I was going to tell my brother and SIL about her behavior yesterday, which would most assuredly be the end of her relationship with my brothers family and her own grandchildren. I also told her that she had to excuse herself from babysitting tomorrow because my SIL has told me she doesn't feel comfortable with my mom and after her behavior yesterday, I don't trust her either. I pleaded with her to seek therapy, but of course she refused. She said she doesn't need it, and that everyone is against her and hates her. Basically, none of this is her fault.
My brother doesn't know about the most recent event yesterday, because we do not want to stress him before his new baby arrives. It's already stressful as my SIL is high risk for giving birth. I really don't know what to do, and neither does my dad. I know that trying to engage her and reason with her is pretty much pointless. But I'm really hoping to hear from others that have dealt with this. I've been dealing with this all my life, being the target of her rage, usually. I've kind of disengaged with her, by things I've learned through therapy these last few years, so it seems she is now turning her anger toward others (did I mention that she is embarrassingly RUDE to people, for no reason sometimes?)
I guess I just wanted to share my family's story and look for any feedback/advice... .it helps to share and talk with people who are experiencing the same situations.
Thank you to all who take the time to read this, I am sorry it is so long, but it was helpful to get this all out in writing. Thanks again everyone.