Mom gives Dad with dementia too much power. Any advice?

Maybe mom would listen to an impartial third party? Call you Agency on Aging for suggestions. Another idea is to find a Geriatric Care Manager to come in and do an assessment of their situation and needs.

katiekay, I would let them be the guide of what they will accept. Otherwise you'll end up feeling a lot of frustration and resentment. My mother and father also had much resistance to changes around the house, like people coming in to help. For years my mother talked of how my father didn't want this or that. After my father died and there was no one left to blame, my mother still had the same resistance. IOW, it wasn't him, it was her not wanting the changes. You may find it is true for your parents as well.

It is easier to just go with their feelings unless it compromises their health or presents a problem. You will probably have to step in more as they get older. I hope they will not be so resistant then.

I so understand your frustration! My mother is a bigger problem than my father who has alz. My sister and I arranged for an independent party to come in and assess my father 7 years ago. She told my mom that dad could not be left alone anymore but she thought that was "silly". She did rein it in a bit and only left him for short periods but she was still adverse to bringing in a caregiver more than a few hours a week and would let go of caretakers she liked (that actually did a lot of things that she could no longer do in the home) because dad "didn't like it". We tried everything to get her to come around and understand that, although his feelings mattered, his reasoning was flawed. Like your parents, they bickered and argued over the most ridiculous things because dad was illogical and mom was in denial.
About 2 yrs after beginning this journey (yes, 2 years!) I finally convinced her that she was cheating herself out of benefits by not letting go. She had to come to a lot of those realizations on her own but we kept planting the seeds. Instead of arguing with her, we gave her "gifts" of help every few weeks. We made up holidays (it was Mom Appreciation Week, or Give Mom a break day) We told dad that he was "helping HER". He was still with it enough to accept and even take pride in the fact that he was allowing it. It didn't always work and he complained but we always made a big deal of thanking him for helping us be able to "do things for mom."
The caretakers (and believe me, I know how lucky we are!) were angels and they would make him feel special even if he was cantankerous. My sister lives in another state but fortunately I was able to live close by and spend a lot of time there. Baby steps is what I can tell you. My mother felt that because she has been married to him for 63 years she knows him better than anyone. That is, of course, true. Remember you are turning her life upside down and try to be sensitive to that. She also was afraid of being taken advantage of and having strangers in and around her home. This is a real fear. They know the stories of unscrupulous people that con elderly couples after gaining their trust. It also disrupts their accustomed way of life. Things can't always be done "when they feel like it" or schedules or habits are shaken up. Nobody likes to be told they are doing something wrong when they firmly believe they are not. In fact, my reason for coming on here tonight was to seek advise on how to deal with some of mom's issues now that dad requires 24 hr care. Having caretakers is no longer the issue since dad cannot do anything unassisted. This is just the beginning of the journey for you and my prayers are with you. I now live across the street and I am in their home every night. I stay on the weekends. Dad can no longer communicate. We know his moods and he is VERY vocal but unfortunately it is no longer English, just garble, anger, and laughter. We live for the laughter. It is less and less these days. It is important for mom to keep him home as long as possible and we will do that but he no longer knows what home is or where he is. (At least we don't think he does) What we do know is that we can try to comfort him when he is scared and we can give him his favorite desert when he needs cheering up and we can hold him when he cries. Mom has had to face some awful truths in the last years but I let her have her denial whenever possible. Just last night after a frightening and frustrating evening we had an ice cream party with dad because it was "We are so glad you are home with us day!." It was mom's idea cuz she thought HE had been through too much. (He slept while she cried her eyes out)
For you my friend...do the best you can. My sister knows I am the lucky one. From a distance things seem so dire. If they are in danger, that is different, but even though I get frustrated at how mom still thinks "he is just being stubborn" or "I can't believe the caretaker gave him broccoli--he hates broccoli!" I watch her stand by his hospital bed in what used to be their bedroom and stroke his face for 10 minutes because "his eyebrows are frowning" and I say we should all have a little denial. Let patience be your mantra. My heart breaks for you but you won't be able to fix this. Even if you don't think they are always doing the right thing don't try to force. Whenever possible nudge her in the right direction. Once we stopped trying to enforce "for their own good and safety" mom started asking. It was agonizingly slow in coming and it still is less than I would like, but it did come once she felt we weren't judging and swooping in on her. Try a little denial of your own, there will be plenty of time for hard truths.

Oh, and keep coming back here! This site saved my sanity (and probably my mom's life) on so many occasions! A lot of times I just spend hours reading thru the posts. Other times I have vented or asked advise. I would not have gotten through the past few years without it! Good luck to you!