Just do not want to be the only one. I am just tired of her honing in on me. I do not mind helping her. I just do not want to become her only chosen option. I work by choice and do not want to alter my life because I can make it easier for her in her needs. How do you deal with someone who has the financial means to hire help and other family members willing and able, but you are the one to get stuck with your elderly mother's wants and needs?
They each have a scheduled evening with him and weekends are open. Set a schedule and stick to it. "Mom, I'll be here on Mon., sibling 2 on Tues., etc.
She'll probably say that none of them does 'x' as well as you, but don't fall for it. She'll get by just fine. So what if things aren't perfect. I know I don't always get everything I want. Of course, I'm like an only child dealing with my mom. Whole 'nother story.
Manage those sibs, girl! And mom too! You'll be happier for it. I know, I know. It's so hard to tell your mom the way it needs to be. I'm still working on that myself. :(
You may not be able to control your mother's preferences and demands, but you can certainly control your own behavior.
Your mother is certainly lucky that she not only has the means to pay for help but that she also has more than one child willing to help. If she won't accept her good fortune, that is her choice, but it does not obligate you to do more than you are freely willing to do.