I cannot figure out my situation though. I provide my mother with all care. I offered to move her to my sister's city or get 24/7 care in her house because it is hard for me to be around someone that lies. I just don't know what to do.
My first thought, and maybe it's not a helpful one, is that part of the problem is "you are still trying to figure out the situation". Instead of this rational thinking, which will get you no where with a pwBPD, I would suggest radical acceptance, and facing that "it is what it is". This is kind of a shift in thinking.
I have always been the strong, problem solver, and reliable one of the family. It hurts my feelings that I do everything for my mother and she treats me this way.
I get it. You are helpful and supportive, but none of that seems to matter or count for anything with her. I can relate. With my mom, the "harder I tried", the worse she treated me. It was a process, but I have transitioned to "letting her" do more (she's 85 and fragile in every way). Despite her telling me what she can't do, it turns out she can do a lot more than she convinced me she wasn't capable of. I had to learn that I didn't have to do everything for her (even though she has a long laundry list of serious health issues). Now that I'm giving her the opportunity (i.e. being less available to do it for her), she's got more confidence. But to get here, I had to suffer through some extinction bursts. Your situation may be very different.
I want to defend myself. I want them to know I know. I want my sister to know the truth. Do I defend or do I walk away letting my mother cloud my sister's perception of me.
It feels impossible to give advice, because we just haven't lived your situation, and don't have the facts or feelings of your lived experience. Having said that, are you familiar with JADEing? Justifying yourself and your actions? Arguing your case? Defending yourself against judgement or attacks? Explaining your reasoning or actions? Generally speaking, JADEing is a good thing NOT to do with people with BPD, because they find this very invalidating, which triggers more intense negative
feelings for them, resulting in nastiness and reactions to our JADEing, and then the conflict escalates. I avoid JADEing with my mom now. I use other techniques instead. But in your case, it sounds like a bunch of lies have been told about you, and you would like to set the record straight. Do I have that right? It sounds like your sister is BPD. Is your mother also BPD? That is a consideration, as is the quality of your lifetime relationship with her. If she has trusted you in the past, that is worth something. I think it is pretty normal to want to share your truth with her. The thing is, if you do that, it would be a good idea to prepare yourself for all possible responses, including a negative one. That would be the worst case scenario, but you would still have stated "your truth". To have the best chance at success if you decide to move forward with that plan, it is best to craft your message carefully, choose your words thoughtfully, state the facts, be sure to stay calm, and keep the message simple. Google BIFF - brief, informative, friendly, firm. Keep in mind that whatever you say will get back to your sister, and twisted against you. In the end your truth may make no difference. They are going to think what they want, and you can't control it.
In the end, what can guide you best, is to think about your own values, and be guided by your values. Do what is most likely to support
your health, because actions and reactions that support
your own well-being is the only thing you can control.
Recently my sister said I should do the cooking and my husband and adult son should help also. Right now my husband cares for my mother's car, her yard, manages her technology, minor household repairs, arranges extensive home repairs, invests her money, prepares her taxes, helps with doctors, entertains her for holidays, birthdays and cares for her like a queen when she sleeps at our house. And he is suppose to cook too?
I can't even begin to think like my sister and I can't even begin to understand my mother's backstabbing ways.
I don't get it. I don't understand
Right. So stop trying to understand what can't be understood maybe?

For me, this was radical acceptance of the situation. The temptation is to JADE, but this will escalate, and make the conflict worse. I very slowly and deliberately began to withdraw from doing the things my mom could do herself. It was a process, and took a long long time for her to adjust. A question I have for you: why is it so important to you what your sister tells you "you should be doing"? What if a stranger off the street said this to you? Would you be more likely to dismiss it? If yes, why is it different with your sister? Should it be different? Maybe change things up a bit, and see if you can react less to some of the things she says - so give less importance to what she says.
My mom used to say things which I referred to afterwards as "barbs" with my H. She was always shooting barbs at me, trying to suck me into some conflict. Conflict was her norm. That's when she's dysregulating, which it sounds like your mom and sister are both going through. Maybe try not to react to the "barbs"? See what happens if you don't react...
Not sure if any of this is helpful. Sometimes just doing your best, is all you can do. If it blows up, they will blame you. That doesn't mean it's your fault. Just do your best. Then reflect, and keep learning.
