I've been researching the whole risk of older people and Lorazepam / Diazepam thing and it's shocking! I had no idea how dangerous those tablets were to older people with slower metabolisms, they don't even give them to the over 65's anymore in the UK because of the risks! It sounds frighteningly why we e had such deterioration of her mental health as it increase aggression, volatility, delusion! It would explain why she's been more prone to falls in the last year or so and her memory was noticeably bad at the weekend, she was very frustrated at times trying to remember words she wanted to use.
It's appalling how lax the medical profession have been , how long have they known about the risks of these drugs on the over 65's yet did nothing! Now we have to see if they handle her withdrawals sensibly or whether that is the next big crisis!
One of the challenges of elderly people with BPD is that sometimes their behavior is related to BPD and also possible it's related to age related issues- like dehydration, urinary infection, reacting to medicines, and also a bit of both, but the physical issues need to be looked for.
When these medicines became more controlled and BPD mother's doctor could not prescribe them to her regularly- he had her go to a rehab program. The program managed the withdwawal but then she signed herself out and refused to go to follow up appointments. At this point, she was off them, and unable to get any more. However, these medicines had been helping her to cope with her BPD- they are not specifically for BPD and they were not given to her for that (she would say other reasons, I'm not sure if she was officially diagnosed with that at the time) but they helped with the anxiety she had due to that.
Off all medicines, BPD mother could not cope at all. BPD has been described as being like having no skin. She was miserable. She also felt shame because now it was obvious that we kids knew about the drugs. We already knew, she just didn't have it out in the open. BPD is a spectrum and people can be different but her anxiety was so high, she was completely miserable all the time. She found a psychiatrist to help manage it- and who was able to precribe these drugs. She was back on them. They worked for her, even past age 65. It was several years later that she began reacting to them.
BPD mother kept a lot of what she was doing to herself. We weren't aware of all that was going on with her when she lived independently at her home. There were some withdrawal events when she took the medicine too fast- taking more than prescribed but since it was controlled, she couldn't get refills right away. One idea to consider with your mother is that her stumbling and memory difficulty could be a reaction to the medicines or that she's taking them more than prescribed.
Eventually, she had to move to assisted living. There, her medicines were kept by the nurses and given as prescribed. Sometimes she'd be fine and other times, she would have very unusual behaviors- not just forgetting words- she was wandering around, not knowing where she was, saying strange things. Sometimes this was because of a urinary infection and eventually it was connected to the dose of Lorazepam, a regular dose that had worked for her didn't anymore. Yet she still had very bad anxiety and so they had to find other medicines that could work for her, some of the other antidepressants in low doses.
It may take some trial and error for your mother's doctors to see what can help her. While I wish, and I know you do too, that my mother wasn't dependent on these kinds of drugs, it became a quality of life decision. She had had therapy over the years but was resistant to it and when rehab and therapy was offered to her, she refused it. Off any medicine, she was completely miserable. What good does it do for an elderly person if they are drug free but miserable all the time? Medicines were the only option to help her cope. They didn't help BPD but they did help with the anxiety.
It may take the medical providers some trial and error to find what may help with your mother. Each person is different and may respond to the medicines differently. It's hard to know what is going on with your mother. Maybe it's the medicines, maybe it's that she's also getting older and more prone to falls and memory challenges, or a urinary infection, getting dehydrated.
I understand your frustration with your mother's doctors. Another issue they may be dealing with is that, doctors respond to what the patient tells them and so if your mother is saying- or not saying- inaccurate things to them- they may respond to that. While I know you are angry at them, it would be better for your mother if you could have a working relationship with them- give them feedback on what is going on with her. It would help them know what is going on with her so they could decide what to do.
Ultimately- no medicine worked to change the BPD behaviors- there is no medicine specifically for that, but they did help with what was for her a part of it- the anxiety,