My partner wants to change my house

This is a petty first world problem but I gotta at least yell it into the void.

I have a fiancé I'm deeply in love with who moved in with me 2 years ago. We both have a bit of autism.

She has health issues so she can't work as much as she would like but even if she could there is still a huge income disparity. Which isn't important to the relationship but comes into play.

I pay for everything. She has a car payment and buys almost all the groceries. Her car is electric so I even pay for her fuel to get around as I installed a Level 2 charger for her. I also pay her insurance health and auto.

I gave her an entire room to do whatever she wants to do with. Draw on the walls whatever. Tear it down to the studs for all I care.

I own the house and furnished it to all match with very nice stuff that was very expensive, but I know she also needs to feel at home. So we got rid of my couch for hers and let her arrange it how she wants.

Her health issues make it so like if the sun is beaming through a window or doorway she can't see well and it gives her a headache. So I pretty much gave her carteblanche to do whatever she needed to do in the living room to be comfortable.

She replaced the window black out curtains with these galaxy ones. Also put another one over the kitchen doorway so the sun can't come through. Put a galaxy carpet runner down the hallway. Painted all the outlet covers and light switches like they were galaxies too. I think it's a little tacky but whatever it's all easily reversed and not aesthetically jarring.

Now she wants to do the bedroom. I'm thinking ok she wants to hang some pictures on the wall and stuff so whatever. Nope she wants to paint all the light switch covers and outlets a wildly different clashing colors.

I ask why? She said she likes to paint the covers while she's sitting on the couch watching TV. I say that's fine I'll buy you a hundred of them and you can paint them just please don't install them because it'll drive me nuts. That went over like a lead balloon.

She kept saying that I told her to go nuts but now I'm drawing a line. I am because I don't like the idea of having to stare at this everyday. I asked why not paint on your canvases? Do you want me to buy you paintable figurines? If you want to paint on the wall so bad you have entire room that I don't care what you do to.

I need to vent because she was being absolutely obtuse about this. She always reminds me of how she hates the house color and my furniture. She gets mad when I respond that if she hates it she can sell it and replace it with the same quality furniture (way out of her budget). Also she would have to pay pro painters to paint the interior as her health is not gonna allow her to do it, and I don't want to/am perfectly happy the way it is. Am I supposed to just let her do whatever, pay for, and smile about it even if I hate it?