Britney Spears rocks a lingerie-like slip dress and red lip in a birthday Instagram post

The pop star turned 43 on Monday, December 2nd

Britney Spears is sexy at 43 years old!

The singer posted a video on Instagram in a lacy night out look on Monday, December 2, in honor of her birthday.

Spears wore an ivory lingerie-style slip dress with an embellished floral lace hem. She paired it with a pearl gold necklace, black strappy heels and a white lace scarf. The pop star posed for the camera and completed the look with a bold red lip.

“Pre-dinner red lips and delicious wine 👄🍷!!!” Spears captioned the Instagram post with the song “So This Is Love” by Disney Cinderella.

In addition to her birthday, Spears has another reason to celebrate.

On Monday, she was declared legally single by her ex-husband Sam Asghari. Their divorce was finalized on May 2 in Los Angeles, according to documents obtained by PEOPLE.

The couple, who married in a fairytale wedding on June 9, 2022, were together for 13 months before calling it quits at the end of July 2023. Asghari, 30, filed for divorce in August 2023, citing irreconcilable differences.

“The divorce was amicable and the prenup was not contested,” a source told PEOPLE about the split in May. “Britney continues to develop her freedom and move on.”

The Grammy Award winner posted another celebratory video on Instagram in October after announcing their split, in which she wears a wedding dress in the name of self-love.

“The day I married myself… I’m bringing it back because it may seem embarrassing or stupid, but I think it’s the most awesome thing I’ve ever done!!!” The “Piece of Me” Singer captioned the post.

Asghari is focusing on his acting career post-divorce and is expected to appear in the third season of Peacock’s The traitorswhich will premiere in January, he told PEOPLE in November.

“It’s the bed you make yourself and you have to learn to lie in it, so it’s part of the lifestyle,” he said. “You just have to keep it positive. You have to stay grounded and understand what the truth is and just live with it and not with other people’s opinions or anything like that.

Never miss a story again — sign up for PEOPLE’s free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories.

The actor also spoke to PEOPLE in March about his divorce and shared that he harbors no ill will toward Spears.

Related: Britney Spears and Kevin Federline’s 2 Kids: All About Sean and Jayden

“It was a blessing to be able to share life with someone for a long time, people grow apart and move on,” Asghari said. “I’ve always hated it when people leave a certain relationship – and at some point they told each other they love each other, sat at the same table and ate (together) – so I’ve never understood when people part ways ( and) they talk badly about each other.

He continued, “That’s something I’ll never do because I’ve had nothing but an amazing experience and a great life, and that will always be a part of my life, a chapter of my life.”