I want my sister to pay half of the household bills.
What does your sister think about paying half of the bills?
I don't care what she thinks, she needs to pay her part.
Although she's family, it's normal that she should help pay for the bills of the places she is living at if she is an adult and is financially able to. Make a detailed list of all of the shared expenses between you and your sister.
I hope she is ok with it.
If you explain to her how you are feeling in a calm way, I think she will understand and be willing to chip in to help. Try not to be aggressive about it so that she is willing to hear you out.