How often do you wash your sheets?

Hey, I'm 13, and even though I know how to do laundry, my mom still washes my sheets and bed spread.

Though, I never sleep with sheets. I always sleep with a comforter over me because it's a lot more comfortable to me. If I have sheets on the bed, I just sleep on top of them.

I'm trying to remember the last time I did laundry.