Kabik / Retna Digital 1 / 10
Kabik / Retna Digital 1 / 10

With this ring ...

Courtney Robertson put the final nail in the coffin on her relationship with Ben Flajnik on Sunday, returning the three-carat, $80,000 engagement ring he gave her on the finale of The Bachelor last fall to the Neil Lane jewelry boutique in Los Angeles.

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(On the ABC reality series, show producers foot the bill for the rings, and contestants are obligated to return the jewelry if and when wedding plans are called off.)

Following one of the most controversial "Bachelor" courtships in history -- she was catty, he cheated -- the California winemaker, 30, and the Los Angeles-based model, 30, announced their split Oct. 5. "We grew apart," Flajnik told Us. "We realized it wasn't working."

PHOTOS: Biggest Bachelor splits ever

Robertson made quick work of rebounding -- caught making out with "Bachelorette" castoff Arie Luyendyk Jr. last week -- but an insider tells Us Weekly her feelings for Flajnik were real.

"Courtney was in love with Ben," the pal says. "She put a lot of work into that relationship -- him, not so much."

Eventually, a second source explains, "She ended it."

VIDEO: Why the girls hated Courtney during "The Bachelor"

As Robertson dives back into the dating pool, a Flajnik pal adds that "he'll date again soon" as well. "He's approached by girls all the time."

This article originally appeared on Usmagazine.com: Courtney Robertson Returns Engagement Ring After Ben Flajnik Split

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