Bill, I am so sorry you are going through this. I first want to tell you that schizophrenia is not at all the same as any type of dementia, as it has to do with receptors and is not a vascular, or brain shrinkage type of issue with the brain. Any type of aggression, hallucinations, or paranoia is different.
That being said, my mother suffered from extreme bipolar disorder during her lifetime and had some bit of schizophrenia (schizo-effective disorder) that accompanied it, but it was very much more under control as the new meds were invented towards her later years.
Then, at about 71, she got Lewy Body Dementia, which is like Parkinson's and Alzheimer's all-in-one. She did initially go through some fear and anger, but unbelievably became one of the nicest people ever to deal with and it was actually a healing experience to take care of her first hand.
She was mostly angry when she was in a rehab facility at first (because she had a horrible fall), but then we took her to by brother's house and I was there with her every day, along with a nurse's aid, and we did have my sister-in-law's mom for a little while. We had some help, so don't blame yourself for having her in a facility. Most importantly, you have to take good care of yourself before you can take care of her. I learned that the hard way.
She forgot who we all were eventually, and it was most hard on my brother. He became despondent and didn't see the point in talking with her anymore--and I will tell you this, no matter whether she remembers you or not, fondly or not, she will always know basic things like love. This does not go away. She will always respond to your love and caring, even if she seems mad at you for now.
My mom was...no offense to the dead, but not a great mom or person during her life, but a wonderful human underneath it all, and that showed up in the end. She was super appreciative our being cared for. Even in the late stages when she could no longer feed herself, or hardly speak, she always could say, "I love you too," when you told her you loved her. You could always hold her hand and she'd grab it back and show love.
Sometimes I think maybe we are not our memories, but we are just living in the present moment because there is no past or present. Memories are for other's. We get upset when we are forgotten, but we can learn from a person with dementia that love is all that matters.
I recommend looking into Memory Bridge Foundation in Chicago. They might have some literature about spending time with people with Alzheimer's and connecting in new ways through art and music, which you can do both with her. You can make her paintings that might help her connect things she was fond of in general ways that can help her overall happiness. This is just a suggestion.
I bought my mom a Goya painting of dancers for over her bed and it helped her because she was a dancer when she was younger. She'd stare at it and it made her peaceful.
I wish you the very best and patience during this time. I have the utmost compassion for you. You are in my heart and my thoughts, Bill.