The couple celebrated their engagement with a bash on Oak & Reel in Detroit on Saturday, Nov. 30
In the first photo shared from the celebration, Thurston posted a picture on her Instagram Stories of a custom sign welcoming guests to the party.
"We're so glad you're here," the black-and-white sign -- which was surrounded by a wintery floral arch featuring foliage and flowers, including red roses -- began. "Celebrating the love of Jeff + Katie."
The photo was followed by a selfie of the pair, with Thurston planting a kiss on her fiancé's cheek as she teased in the caption, "Did we just get married?"
However, Petal + Grain, the vendor who created the sign for the couple, revealed that it was their engagement party as they reposted Thurston's photo on their Instagram Stories.
"So excited to work with @thekatiethurston for her and @jarcuri engagement party 🤍," they captioned the post.
Thurston went on to share a carousel of photos from the bash, which was held at Oak & Reel in Detroit, with the caption, "About last night 🤍."
In one sweet shot, the pair posed at a dinner table together as Thurston flashed her sparkling engagement ring, while in another the two clinked their glasses together as they gazed happily into each other's eyes.
The reality TV star dressed fittingly for the occasion, wearing a glittering white dress and white silk bow in her hair, along with sparkly drop earrings. Meanwhile, Arcuri looked smart in a crisp white shirt and light beige suit.
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Thurston and Arcuri announced their engagement on Sept. 15 in a joint Instagram post. Along with photos from an engagement photoshoot on a beach, the final slide of their post featured the moment Arcuri proposed.
In the video, Arcuri could be seen reaching for his back pocket, kneeling down on one knee and pulling out a ring as Thurston covered her face with her hands in shock and nodded a "yes," before the duo embraced.