Deep breath... the pillowcases get changed weekly, for sure, but the sheets? FYI, TMI, I don't even get into the bed... age and hormones say sleep on TOP of the bedspread, with a throw for warmth as needed (If you don't get this, wait til you are 45

) Heck, I've suggested to DH that we just rotate the mattress after a couple of weeks so he can sleep in the "clean" side
And honestly, the dog IN the bed is just disgustingly gross.

Dog hair and drool, feet that have walked all over the place, possibly fleas or ticks, noses, muzzles, and tongues that clean not only your dog's body but have been you-know-where on other dogs?

Gimme month-old sheets ANY day!