BPDFamily.com

My SO is undiagnosed BPD, she has a tendancy to fly off the handle at her daughter sometimes and can say the nastiest of things, we have been together on and off for 8yrs and i regard her daughter as my step daughter. I hate to see her daughter cry because of what her mom says, i can only imagine how her daughter must feel to hear such words being spoken to her by her mom whom she adores.

I know most of what her mom says is due to her illness, she will quite often ask me, do you think i was too hard on her - i know this is asked out of guilt because she often will realize after the fact that she was over the top.

Most of the time i do tell her that she went too far, and of course she tries to flip her guilt/anger on me, which i am getting better at not accepting.

My question is, how do i deal with this situation - i do not want to step on her mothers right to discipline her child, and on the other hand i don't want her poison being directed at her daughter whom i love/care about very much.

I  usually agree with  the point she is trying to make ( stopping bad habits ) but she tends to take it to the extreme rather than dealing with it in a rationale manner, i am worried for her daughters mental state in the long run having to deal with her mom's outbursts.

There are many mechanics at work her and i am just a bit confused at how to deal with them. Any thoughts would be appreciated.    

How old is her daughter and how has she come to live with her mom?  My BPDw's son lives with us now because his APD father is awaiting trial this month and may go away for awhile... .   Basically the lesser of the evils at the moment.  He was supposed to go back after summer break and never left.  BPDw is still reeling from that and is finding it hard to cope with her son living with her full time.

D is 8, always lived with her mom, was basically raised by her grandmother until she passed away 3 yrs ago, they all lived in same home together and g-ma was always there for her. D is suffering from separation issues still and is very clingy to her mom. When her mom yells at her, fine then i will leave and never come back, will that make you happy you little brat - i could just throttle her when she says that, oh, and i did not mention that my SO is an alcoholic to boot, i have been dealing with this for quite some time. Just in the past yr her D is starting to mature and form her own opinions which quite often contradict her mom's opinions and hence the arguments and my dilema.     

I should note, my SO loves her D to death, she would do anything for her, its just that the illness sometimes interjects itself into the situation and as you are well aware causes issues. Overall she is a really good mother, however as her d grows up she is starting to question some of her mothers decisions and actions and as we all know, a pwBPD never really likes anyone second guessing them.   

Mine has alcohol issues also and has many run ins with her son about it.  Her classic answer, I'm an adult and can do what I want!  He is so embarrased by his mother and her bad choice of friends as am I.