She also reads voraciously which she never did before. She likes American history books. She tends to think it is our family history when it is not. Nothing is scaring her though, and she still knows who everyone is and is not doing badly at all. Just wondering if any of this has to do with Alzheimer's.
Refolding clothes can be soothing to the sense of touch. It can provide a sense of control over the environment. It can be reassuring to be in touch with familiar items. My mom and husband each had dementia, and they both loved folding small items of laundry. My mom also loved sorting things -- another way to create some order out of chaos.
If your mom is doing this out of boredom, then be glad she has solved that issue in her own way! You could ask her to help you sort your button box or to match up socks right out of the drier or some similar task as a little diversion, but if she prefers sticking with her drawers there is nothing harmful in that!
One woman I know of spent hours handling her jewelry. Dealing with familiar objects that are textured and/or pretty seems to be popular among persons with dementia.
The delusion that history books are about her family is kind of charming. There is no need to correct her, unless it causes her distress.
I have been working with seniors off and on since college. My last job was with AARP Health doing Medicare Supplements and now I work with Jitterbug cell phones. I am trained and used to dealing with this stuff. Frustrated!