How do I encourage good behaviors without being pushy?

Man, that’s a tough situation to deal with. I get your concern, but I don’t know of anything you can do other than your current support.

Has your sister mentioned Hospice or Palliative care? I might get that information in advance. When someone is very ill and mobility is an issue, you really need backup nearby that can come quick. When my dad took a turn for the worse I needed a hospital bed immediately, since he couldn’t maneuver in the bed or get up. And, I was up all night 24/7 providing care. It was a very shocking experience. Even after I got some help.

I hope you’ll get some responses from those who have gone through what your sister has. I haven’t dealt with that. I know it’s a very serious condition and her attitude about it is understandable. Does she take meds that might help with anxiety or depression?

That's too bad that your sister is having such problems! I feel sorry for her and for you too. She had a lot of surgeries and chemotherapy etc. Possibly some of her symptoms are from the side effects of those medications. Perhaps she should take a break from them for a while. You said she was tired all the time. Is she getting enough iron and vitamin B12? They give you energy. I'm 79 and take both iron and B12 tablets daily and also eat a lot of foods with iron and B12 in them. It helps immensely.

Celia16's suggestion of Hospice and Pallative care is a good idea to look into. You need some help.

Another source of help is God. He's there for us. Just ask for his help in curing your sister. God made your sister and he can fix her. I'll say a prayer for both of you.
I wish you both the best.
PML

@eliza4 my heart goes out to the both of you. Sorry.- this is going to be long. I too have tried to find a way to slow things down, but sometimes there is nothing to be done that will help. In the end it is her decision. My sister (76 and with other issues) passed away 2019 from glioblastoma. She worked in the caregiving field, so once she regained her senses after the first tumor was removed, and during which the glio was initially diagnosed, she declined further treatment. She made her peace with it and was rarely angry, she chose to enjoy what was left of her life. She had 1 good year, Before she started to decline rapidly. Not everyone will be able do that. Everyone is different. However in the last 6 months my sister became increasingly non mobile. Either she did not want to discuss it or she didn’t have the words for what was happening to her. I feel that she was losing her sense of balance and was in fear of falling. But also her brain stopped making the necessary connections. She wanted to pass at home and we were able to support that wish because we also called in hospice. They have a lot of experience, and also assisted with my father’s Alzheimer’s journey. They will support you also- because you need it too. If she, you, or hospice feel pain medication is in order, please pursue it. And though I have also cared for 2 of my family members at home until EOL, it is a long brutal job. My other 2 family members we kept at home as long as we could, but in the end they needed more care than I could provide, so I had to take them to the hospital for their own comfort. I am the last one left, but I learned a lot along the way. I know you love her, but you must not feel it’s a failure to ask for help. I am now in the position where I have to make the same decision as my sister (not glio-but I almost wish it was) I know my decline will be slower, I think I might have a few good years left. I am now 70, still strong enough to be enjoying life. I am choosing quality over quantity. It has brought me an unbelievable amount of peace and gratitude.
The learning I received from all those years of caregiving was this: we can only have so much impact on someone else’s behavior. If they are in this position = let them. Let them lie in bed, let them smoke(outside?widow open?) , let them eat chili, let them have whatever they want. All you can control is yourself. Try not to make yourself too crazy with all the would have’s, could have’s, should have’s. (Says the person who definitely did)😂
Do what you can, because you will look back with few regrets. But realize you are not super human.
I wish I could soothe your soul.
🫂s

Thank you for all the kind comments and suggestions. We've talked to her doctors and they've gently backed me up because so far the treatment is keeping the cancer in check. It won't forever of course, but she's not in imminent danger of dying--they think they can get her a couple of years. She and I also had an honest conversation where I told her that my fear is she's going to become immobile and that I'll have to send her to a care facility. That it will break my heart, but I can't care for someone who is bedridden for 1 - 3 years. We'll see if any changes come from it, but I feel better knowing I've done what I can.

@Eliza Like the others, my heart goes out to you. You are in a difficult and most challenging situation. As a caregiver for years my hardest and most challenging was my mom. There are many painful factors in your situation but what may or may not be of comfort is that my mom said to my sister when she came to visit (out of state) "if I have to suffer so does she!". (She refused to wear Depends and would almost deliberately poop walking down the hall - making a mess on carpet and walls - the cleaning up was endless through the night as well as day --chemo reaction.) Then, of course, cleaning her up as well and keeping the house clean was unending. She eventually wore the Depends, but I bring that up because it was that I was her daughter and she was different with me. Maybe it was true that she took advantage of me because I WAS family and did want me to feel her suffering by making it harder on me and refusing anyone else to come in and assist with her care. I honestly will never know the answer to that; this may be of no help whatsoever to you, but I think it is worth sharing as it may help or resonate with someone else who has had a difficult person to care for who happened to be a blood relative. I agree with all the helpful comments here and I also am amazed at what family members are willing to do for their loved ones. You have been a lifesaver to your sister, she may never be able to tell you how immensely important you are to her as she is, as you say, in so much pain right now. People who suffer with pain for example, fibromyalgia, have a similar kind of reaction to the pain and the pain is so bad at times the only thing they can do is stay as still as possible and wait for the pain to go away. Music is helpful and YouTube has some amazing healing music for neurological pain. ("A 2015 study in scientific Reports found that music can reduce pain intensity and unpleasantness by modulating activity in areas like the amygdala and prefrontal cortex." Also, music can reduce cortisol levels "and promotes relaxation by calming the autonomic nervous system. The YouTube ones that I am referring to are the ones with binaural beats or specific frequencies, such as 432 Hz or 528Hz).
Also, the distractions are helpful. For example, Insight Timer app is a good resource and completely free (there is a buy-in for those who want to be on the Plus--but totally unnecessary as the free stuff is excellent), but there are people who read books and tell stories which is helpful if your sister was willing to try them. The time she can delve into some of these kind of distractions will hopefully give you some respite time for you to take care of you. As caregivers, especially live-in ones, it is SO important to take walks and breathe fresh air, talk to a friend, etc etc etc. All the things I'm certain you do already. Just know you are not alone. My heart goes out to you and your sister. Tough times for sure. All the best--

https://bio.belightcare.com
Hi - I have found a vast resource of tips and caring suggestions from Adria Thompson - who is the founder of Be Light Care. She is a Speech Language Pathologist and instructor.
I found her on Instagram while searching for help for my Mom, who was declining from dementia. But I’ve also found good insights for the ongoing care of my daughter who is a stroke survivor. I can’t imagine what I would have done without the validation and knowledge I gained by following Adria.