The Bachelor Winner Courtney Robertson Returns Engagement Ring

Robertson -- who called it quits with "Bachelor" Ben Flajnik last week -- hit up a Neil Lane jewelry store in L.A. Sunday to say sayonara to the 3-carat rock.

We're told the ring ended up back at Neil Lane since "Bachelors" and "Bachelorettes" don't foot the bill for their own marital swag -- i.e. when the relationship goes away, so does the bling.