My grandfather is in the final stages of Alzheimer's in a hospice home.
You said "I have had a great sense of healing", which is important because it sounds like you're doing all you can. It's a disease that kills the mind before the body passes. So while you think it's vital for your healing to visit, what's most important for her probably are comforts in line with her level of cognitive functioning: to be physically comfortable, to have physical contact, to have soft words and music and the like. I believe, and not in a demeaning way, it's a disease that returns a person to infancy where simple things bring peace.
I also want to let you know that my grandmother visits my grandfather many times a week and is beginning to show signs of dementia. Stress and desperation can make a person very sick: it's decreased the quality of life for my grandmother and initially triggered and worsened my grandfather's Alzheimer's at the early stages.
I wish for any caregiver in yours and my grandmother's situation that they know when to limit their care and heartache when their personal "sense of healing" is compromised. It's within a loved one's nature (especially for women) to be self-sacrificing for our friends and family. Just be conscious that you don't sacrifice beyond your means. Your quality of life is precious and a gift worthy of great protection too.
Finally, you mentioned "I don’t want her to die without being at peace about it". In my opinion, peace in another isn't something you can control. You can provide everything to facilitate peace (a quality care home and the basic comforts mentioned above, so long as it doesn't lower your quality of life) but you can't MAKE her feel peace. Whether you believe it's God-given or from an inner source, your mother is worthy to receive and able to find it, no matter how damaged her mind may be. Worrying about her finding it won't bring you peace or help you in facilitating peaceful surroundings for her or your family. Everyone searches for peace and I'm sure at the end of life she will be searching inwardly too. That, I hope, you can find peace in.
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