I used to be a mule as well, but it turns out I never touched most of the stuff I dragged around. My handbag contains:
phone
reading glasses
small flat leather zip-pouch with wrist strap for cash and debit card
small thin metal snap-lock case to stack credit and ID cards in
one chapstick
one lipstick
a couple hair elastics
I just need a little extra space for sunglasses IF needed, and the key fob if I'm driving. So if you come to me for tissues, deodorant, saline, tape measure, stain stick, umbrella, shopping bag, sunscreen, headphones, nail polish, clippers, perfume, brush, bandaids, mints, gum, wet wipes, aspirin, or a pen........ I'll just point to Suz!