Oh Chopin it seems that the current situation with DD1 is an intense, dysregulated, emotional valency that is unconsciously very familiar to you since you have described your challenging family history.
Lots of layers of trauma, drama, tension, unresolved conflict, betrayal at play with codependency dynamics - always trying to “fix” or contain the addict or PD. Trying to keep so many emotional plates spinning and different people happy all at the same time to avert crisis.
It’s a family system that sucks members into to be over invested and compromising of their own boundaries, values and sense of self.
Lots of anxiety, ruminating, hand wringing, frustration, exhaustion, walking on eggshells, self sacrifice, over responsibility and total a imbalance in favour of the disordered person in the family.
If you look at your own DM do you see a way that she could have lived differently? Could she have detached from the worry, escalating issues and abuse which was all ultimately futile? Could she have lived a more joyous, lighter life, more engaged mindfully in the moment and the good people around her rather than be tormented and preoccupied with your DB and her DH?
Also how was it for you watching your DM suffer her whole life? Would it have been better for you to know that she wasn’t consumed, eroded and depleted by it all? Do you think that DD2 and DD3 need to have this same worry about you?
It feels a relief to read that you are getting specialist grief counselling because that is what is right in front of you and is your sole focus.
It is your task just to survive this tumultuous period of deep mourning. I suspect that you have always been a very proactive and productive woman and it’s maybe counterintuitive for you to now know that the work of grieving involves rest, sleep, dropping down into the emotion and going with the erratic flow of grief emotions. Don’t resist the grief pain - you have to feel it to heal it. It is not an indulgence or petty - it’s a process to endure and ultimately you will move through it to a different place in your own time.
Doing much much less to achieve more.
Mostly it will be all consuming, excruciating and exhausting - that’s why you need to consider yourself overwhelmed and fragile at this time and not engage or expose yourself to even minor additional stress for at least the next 18 months.
Self compassion with permission for self care.
Try not to second guess, doubt or minimise your feelings - they are real - you WERE upset about DGD birthday - why would you not be? It seems you feel you have to blunt your emotional reality to suit your DD1. You don’t have to do this. You can feel in full range technicolour and intensity because that is what being truly alive is about - BUT when, how or if you to interact or share this with with your DD1 is another choice.
It seems that this is taking up a disproportionate amount of your finite emotional capacity, headspace and time and probably physical strength for very little reward. You would be better to conserve and redirect that effort to focus on grieving for the untimely death of your DH.
You can’t be in two emotional places at once and if you overload your system you will become very ill indeed and may not bounce back for a very long time. Significant MH episodes can last years and years.
It seems that you are not going to get any answers, acknowledgment, apology or change in behaviour from her/them or the RS you want. Currently you have v limited controlled and monitored contact - technically more than in the past when you were ghosted. I think that this is as good as it is going to get sadly and it’s not ending anytime soon.
I wouldn’t let it dominate your own emotional health, the priority of grieving or your life with your DD2 and DD3 any longer because it will just continue to pollute and erode your lives - with the exact same outcome. I also wouldn’t be encouraging your DD1 to be involved with the family because her and LB will ruin every single event - like they did with DD2 graduation.
Protect your family from their behaviour. I also read recently that the NPD and BPD coupling is classic and very powerful as it directly feeds each other’s needs and issues.
If you suspect that your DD1 is emotionally vulnerable and has some BPD traits then this book might help you to understand her behaviour and cope better.
It is written by a highly regarded medic and was recommended on another thread. It has a preview where you can read a lot of the content.
www.google.co.uk/search?q=when+your+daughter+has+bpd&ie=UTF-8&oe=UTF-8&hl=en-gb&client=safari
I hope that you can allow yourself to know that you will always love your DD1, that you have compassion for some potential undiagnosed instability but that she is has enough agency to conduct her own life and at the same time her poor behaviour towards others is not acceptable and as she is so volatile and emotionally dangerous to you at this time it’s appropriate that you withdraw for all your sakes.
It feels like you walk an exhausting tight rope with her and the best outcome is this detached vanilla fake RS where at least you are in contact - however if this is too exhausting, anxiety making and unpalatable for you then you can choose to take a further step back.
You have endured an awful lot in your life and you continue to do so - cut yourself some slack and be comfortable doing so.