'Teen Mom 2' Star Jenelle Evans Calls Off Engagement to Gary Head

Just two weeks after getting engaged, on-again, off-again "Teen Mom" couple Jenelle Evans and Gary Head have called it quits once more.

"He hooked up with a girl while they were on a break and she just found out and flipped out," a source explains to Us Weekly of the pair's latest split.

The MTV star took to Twitter to rant to her followers about how Head took one of her necklaces.

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"Thanks to Gary Head for stealing my $300 Tiffany necklace . . . What marine does that?" Evans, 20, wrote.

Evans said Head has yet to attempt to take back her engagement ring -- and assured her followers the two talked to the police, who told her the ring is hers "unless [Head] takes me to civil court."

Head, for his part, is set on holding her necklace hostage until he gets the princess-cut solitaire diamond bauble back from his former fiancee.

Tweeting that Thursday was "the worst day ever," Head told his followers that Evans' "necklace is at her house hidden until I get my ring back."

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Despite their bitter war of words, an insider close to the Teen Mom star tells Us this breakup may not be for good.

Admits the source, "I could see them getting back together ... or her running to [ex-boyfriend] Kieffer [Delp]."

This article originally appeared on Usmagazine.com: Teen Mom 2's Jenelle Evans Calls Off Engagement to Gary Head

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