I am currently my mother and father's POA. I'd like to give up doing it for my mother. What can I do if I don't want the job?

Thanks for your answer. I appreciate this support so much. I wasn't clear on the dynamics of our family so I will clarify. I have a half sister whom I do not have a relationship with. She is my fathers daughter from a previous relationship. She has basically had it in for me my whole life and we've not spoken for 3 years. Im in my late forties now. My full blood brother lives in another state. He used to live here but decided moving away from this mess to a sunny location was a wiser choice for him and his family.His wife doesn't seem to want any part of dealing with my folks. When he left my folks were in better shape than now. He left for work though he lives in another state and works from home. He visits twice a year and this last visit was volatile. He must feel some guilt for leaving as he refused too let his children leave my parents house whole visit. Refused to let cousins play unless we went there. The home is a problem for me. He feels warm and fuzzy there but I feel its a place of deep conflict and bad memories. I tend to stay away to protect myself mentally. My brother doesn't respect this boundary. Ive done the best I could do for my folks here while tending to my own large family. When he left I assumed we would in a way be coparenting my parents as they aged, Ive tried to communicate with him on several issues but he never responds me or ignores. Had his wife communicate to me he simply doesn't know what to do with the info I text him. As I said he returns a few times a year to relive his youth and assumes all is like before though its not. He doesn't get the yelling screaming manipulative mom that me and my family sees. He gets the mom that is catering to her fav child. My mom is a narcissist that lacks empathy or compassion for me. She has several other things going on mentally but its difficult to diagnose because she manipulates drs. She has never thanked me for finding her good doctors or giving her best care as my husband is in the industry.
I have spoken to my folks about assisted living. they both refuse though my dad would agree to move to smaller place not assisted. She refuses to leave home because she doesnt want to put up with my dad in close quarters. We had a fam mtg with doctors recently where they were told moving was best option. My dad freaked out and my mom seemed to listen but after appt went back to denying there's an issue and refusal. Our social worker that works with my folks geriatrician will definitely be my next call.
As with all fam issues ours are multifaceted. My mom is mentally ill and I as of now have two siblings that only show up for theatrics. Im basically feeling burned out and disrespected by my family. Ive stopped speaking to my brother and his fam. My mom stoked arguments instead of making things better. I wonder if she does it to get back at me..... I don't know. I do know Im at end of my rope and as of right now just want nothing to do with my side of the family. My mom is at the root of this. Im at a loss..