I just found out that mom has not only been wearing the same clothes for several days out of the week, but sleeping in them too. What do I do?

Mom is 81. I had to nicely tell her that she's wearing dirty clothes to bed, and 'my mom' always told me to wear my clean pj's to bed. I understand she lives alone, and if she's not going anywhere, what's the sense of changing clothes, somewhat, but in this instance, she wore the same clothes to the cemetery, and two days afterwards, PLUS wearing them to bed. I had to shame her somewhat. It gets hard, because I don't want to yell at her! Let me finish by saying she lives alone.