Just 74 days after they met, Countess LuAnn de Lesseps’ business exec boyfriend, Thomas D’Agostino Jr., slipped an 8-carat canary yellow diamond onto her finger February 5.

“He proposed in front of our fireplace,” the Real Housewives of New York City star, 50, told Us Weekly Video while visiting our New York office. “He planned to propose on Valentine’s Day, but he couldn’t wait!”

Now, the “Girl Code” singer and the CEO of Smart Source, 49, are eagerly planning their big day. “I want a big blowout wedding!” de Lesseps, who recently jetted off to Vail, Colorado, with D’Agostino, admits. “Lunches and dinners and parties on yachts.”

Still, she can't guarantee all her RHONY cast members will come out to celebrate. Before he was introduced to de Lesseps by mutual pal Dorinda Medley in November, D'Agostino went on dates with Sonja Morgan and Ramona Singer! "They're attractive women," she says. "He was a single guy. It's a very small circle in New york. But I am the one walking down the aisle. Not them."

This will be the second marriage for de Lesseps. The Bravo vet was previously married to Count Alexandre de Lesseps from 1993 to 2009. The exes share two children, Noel, 19, and Victoria, 21.

So where and when will they say, “I Do?” And which of her RHONY costars will be a bridesmaid? 

Watch the video above! For more details on de Lesseps' engagement, pick up the new issue of Us Weekly.

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