Mom expects me to do it all with no help from my sister. How can I change this?

It is so difficult when a parent's retirement and care plan is one (or all) of their children. Many on this forum have been "assumed" into the caregiving role. You are not obligated to take this on. Neither is your sister, so please stop asking her.

You are operating from within the F.O.G. (fear, obligation, guilt). You do not have to accept this. The only person you have control of is yourself. The caregiving arrangement only works if it is working for both parties. You have come to realize it is not working for you. Therefore YOU need to make a decision on what comes next. Cancer or not, your mom must accept and finance outside help, or transition into a AL facility. You can resign as her PoA (if you actually have this authority). If you think it's bad now, just wait. Maybe read some of the other posts under the Burnout topic on this forum to understand that you aren't going to rescue her and if you stay you will be ground down to a nub. You will need to make a decision that feels very difficult, and is emotionally, but you must take action. I wish you much courage, wisdom and peace in your heart as your set up a healthy boundary to protect the rest of your life.

I myself would be not a very good support to someone who told me that I am responsible for their illness, no matter it is pure nonsense to say something like that. After all, if you CAUSED an illness, your being thee couldn't HELP it, now, could it?
You cannot change your Sister and your problem is not with her. It sounds as though she has WISELY moved away from her mother whatever her own reasons. You can only make decisions for yourself.
I would sit down and tell your mother that you can no longer be responsible for her many needs. That you will be able to help out much less than you have been and you will require sufficient notice for drives to appointments and etc. Supply your mother will needed phone numbers. Others such as American Cancer Society will direct your mother to volunteer services available to her.
Many people struck down with cancer do not have children who can help, who live nearby enough to provide any support. Your mother would do well I think to learn what life is like when you have no one to help, or when you abuse your caregiver to the extent they choose to withdraw a bit.
I am certain that your mother is having difficulty dealing now; that is not an excuse to be cruel to others, and especially to a daughter attempting to help. You would be wise to step away. Your mother is using pain and guilt, and attempting to change you into a whipping post. She would do well to understand where that may work against her.
I wish you good luck.

Well, if it helps, you’re not alone. We are two sisters. Live same distance away. I do 95% (or more?) of everything. Sister swoops in when there’s something in it for her. With her, I’m nearing radical acceptance. But dad goes on and on and on about how busy she is and that he doesn’t want to burden her. She’s busy telling everybody how busy she is... It’s super frustrating that he goes on and on to me about how much stress she is under. Picture eye rolling here...

The good news is that she can manage things at home okay, for now.
The awful news is her telling you such a horrendous LIE!

As for sister helping, don't hold your breath. She's already declined. Regardless of what your mother thinks or says, even if mom was on board, I doubt your sister will help. I had to get past that with TWO brothers. The more you focus on that and get angry that she does nothing, the worse YOU will feel. Your frustration and anger for sibling not helping does NOT hurt the sibling.
Let that go.

I agree that you should be working on getting a POA in place. Since it doesn't appear that your mother has dementia, it should be easy enough. If she balks, focus on her health and say it's only in case you are in the hospital, so I can manage things for you. It really is in case someone is incapacitated, so that their bills get paid! Even though you have the healthcare proxy (presumably through the doctors/hospital), might as well get the MPOA done when DPOA is done - then if she ever has to see a different doc, paperwork exists already!

With cancer, she probably has a number of appts. If things are going well, perhaps they can spread them out a bit more? I know what you mean about the hearing - sometimes even when their hearing is okay they don't quite understand, but my mother's hearing is really bad! Hiring someone would be primarily for taking her to appts, but as you say, you need to be there to know what is said or to be done. Is it possible to do some of these appts as virtual? If they don't need to actually touch her, just check in, maybe see the incision via the virtual display? Check with them. Medicare does pay for these.

You wouldn't want to hire someone to handle the paperwork - and yes, I know that can be a lot too, esp if you are still working. I was laid off and decided to retire then, which was best for me as I could not have continued working and doing all I did/do for my mother!

HOWEVER, being sent home with a drain and any other medical types of handling, they should have set you up with home nurses (not full time, they just come in, can check mom's vitals and do the necessary deeds with the drain!) Medicare should pay for this service, esp if she is homebound, which I would think she is! It sounds like perhaps she is past that, BUT, anything else she needs like that, ASK the doc to set it up! Medicare will provide a very limited amount of in-home help for personal care, so don't be afraid to ask for it!

I wasn't even her age, but begged to go home after weeks in the hospital. I was on TPN (IV nutrition, not allowed to eat) and several heavy duty IV antibiotics. They DID set me up at home with a pump, a feed "bag", shipped antibiotics and feed to my house, nurse came every day to check vitals, set up feed bag with vitamins, weekly or so clean the "port", draw blood for testing/adjustments of antibiotics, etc. It is MUCH less expensive for them to send a nurse for a short time than it is to keep me in the hospital! It was SO much better being in my own bed, with my kitties!!

So, here is the summary:
1) Forget about getting sister to help. Let that go. Waste of energy.
2) If mom says hateful things, try to overlook them. If not, try some humor.
If my mother did things like that, I would turn it around on her and say
something like 'Sure, I gave that to you, keep it up and I'll do it again!'
Probably best to just let it slide. Avoid topics like sister that might rile her.
3) Work on getting DPOA and MPOA.
4) See if you can reduce the frequency of Dr appts, or make some virtual.
5) If mom needs any kind of personal care, ask the doc to order it and get help!

Wow. What a narcissist you are dealing with. Both of those comments as well as the level of reaction (flies into a rage) are way out of line with normal behavior. I don't have any action plan to offer you except that when she goes back to the hospital (and she will most likely), have your plan made. Read from a script that you wrote in advance if you have to: "No, my mother cannot come to my home. Yes, she can go into a rehab facility and go into a care home/hospice as needed." I don't have first-hand experience but one of my closest friends was married to a narcissist for 17 years. No matter how much you give and give and give, you will never get credit for it, your next mistake will never be forgotten, and you will always fall short. She will keep you jumping through hoops. I'm sure she has "trained" you over your life that this is what you have to do -- take and take and take. Please give yourself grace and say no. YOU DID NOT GIVE HER CANCER FOR THE LOVE OF PETE!!

“Mom, if I am responsible for your illness I think it’s best that I distance myself from you.” Period! Is she needs assistance it would be in her best interest to call her other daughter (your sister). Don’t answer her calls. Don’t cave in! Next you and your sister need to meet and confront your mother telling her that she needs to move to an AL. You are the weak one and your mother knows this. Don’t allow her to manipulate you any longer. Free yourself!

I think that you have every reason to run. I am so sorry that she laid her cancer diagnosis on you, that is a bridge to far and she just ruined any help available from you, in my opinion. I would tell her that I don't want to cause her any more illness so I will be stepping away and hope it works out for her.

Saying that to you is abuse and you should not tolerate it for another day.

Let her figure out how to get her needs met.

Great big warm hug!

Short answer: Run away. You are being taken advantage of. Give Mom sis's number and leave for a week or more. Just because your Mom has cancer doesn't mean you have to be her whipping boy. Stop doing this to yourself!

Your sister is letting you do all the work. Your mother is over burdening you and trying to guilt you into doing everything. Both of them are being unfair on you. To protect your own health, start saying No to some of these demands. Make a list of all the help you provide, decide which of these you are prepared and able to do, then give your mother and sister the list and ask them to work out who will do everything else that you cannot do. Expect tantrums, shouting and other bad behaviour but stay firm about how far you can help and don't give in. The suggestion from your mother that you are responsible for her cancer doesn't even merit a reply to her. If she repeats this, walk away. You don't deserve such abuse.

Run away! I did and I survived.