Britney Spears Is 'Ecstatic' About Sam Asghari's Surprise At-Home Proposal, Says Source

Sam Asghari Instagram Britney Spears and Sam Asghari

Britney Spears is feeling "Lucky!"

After her longtime boyfriend Sam Asghari, 27, popped the question at her Los Angeles home on Sunday, a source close to Spears, 39, tells PEOPLE exclusively the singer is thrilled about her future with the actor.

"Britney is ecstatic," says the insider of the pop star, who giddily showed off her brand-new diamond ring on Instagram.

Spears and Asghari — who first met on set of her 2016 "Slumber Party" music video — "are deeply touched by the support, dedication and love expressed to them," the fitness enthusiast's manager Brandon Cohen told PEOPLE in a statement.

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Cohen added that Spears' new bling was designed by NY.C. jeweler Roman Malayev.

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Asghari has been by the singer's side during a difficult year in which her conservatorship has been thrust into the spotlight.

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In August, she praised her future husband on Instagram for helping her through the "hardest years of my life."

After an explosive court hearing earlier this summer, a friend of the couple told PEOPLE Asghari and Spears have long been ready to settle down together.

"He's ready for marriage and kids with Britney and is serious about the relationship. She wants to take that next step and have that full life with him," said the friend. "As a couple they've hidden how they've really felt even from people close to them because they were anxious and scared, but now it's all out there."