Can I Suspend Time For My Mom?

My mother has been diagnosed with early onset dementia.
It’s been steadily getting worse over the last five years which is something that we were prepared for, regardless of the medication.
The problem is, I don’t live close to her, so I’m only able to see her once or twice a year. Because of this, I notice the differences more so than anyone else.
In May, I’m flying back West for a visit; and I’m scared.
I already feel as though my mom is slipping through my fingers, and it breaks my heart.
How do you prepare yourself for this?
She hardly ever cooks anymore because she can’t remember where things are located in the kitchen and gets frustrated. When she does, she can’t follow simple recipes anymore. She’ll forget she added in one ingredient, so she’ll double that up, and completely forget a step along the way.
Although she still has her driver’s license, my dad makes sure that he drives her where ever she wants to go. There will be no more just getting in the car with her to go run errands, because she would insist on driving.
It kills me that I live so far away.
I’ve considered asking my husband about moving back, but neither of us want to do that. We hated living there, and are finally on the right path to reach our dream. I know that the last thing my mother would want would be for me to give that up, and move back because of her.
I want to just kidnap time when it comes to my mom. I want to remember all the wonderful things that I know we will eventually lose all together.
Like playing a game of cards with her. It’s a struggle for her now, so I know in the next year or so, that will be out the window. Or baking Christmas cookies together. Sure, we could with me taking over the making of the dough, but it just won’t be the same.
I feel like a little toddler throwing a tantrum right now, but I can’t help it. It’s not fair.
I know we have to adjust to her disease, and I know I can.
But, my mother is disappearing piece by piece, and although my heart is broken, it is something that I will have to deal with and accept.