Alzheimer Always Tired

My mother's lack of sleep is a total mystery to me.
She cannot understand why she is awake late at night and too early in the morning. She says she lays there thinking but cannot remember about what. I think she is too hot & stuffy because she refuses to leave her windows open- ever- because, you guessed it, it's going to rain...NOT !
There are alot of articles about lack of sleep and this disease but the only thing I see people doing about it is sleeping pills.
I have errands to run today and I called her to ask her to join me and to write it on the calendar. Of course when it's time to go two hours later she is still in her pajamas. At least I am learning now to not expect her to be ready, but to re-call her so she will stop watching tv and get going.
I know bringing mom with me will be like dragging a wet log around, but she was enthusiastic about getting out.
Thank goodness for antidepressants.