Kristin Cavallari dog hotel dog lunch the hills dress

Jay, who?

Kristin Cavallari may be fiancé-less, but she's not sitting home nursing a broken heart with a pint of Ben & Jerry's.

In fact, the former Hills star couldn't stop smiling as she hit the streets of L.A. in a black one-shouldered maxi dress, tan belt and pink-accented black Wayfarers.

Getting errands out of the way, Kristin dropped her adorable pup off at the doggy hotel before grabbing lunch with a pal at West Hollywood's Café Med Thursday.

The bubbly blonde appears to be moving on from ex Jay Cutler fast. Find out what she just sent him ... after the jump.