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By Kat Giantis

Now that Nick Lachey has finally popped the question to longtime love Vanessa Minnillo, many are wondering how his ex-wife, Jessica Simpson, is reacting to the nuptial news. After all, it was just last month that Simpson supposedly took a potshot at Minnillo after running into the couple at a Los Angeles restaurant.

And while the sunny blonde has been shouting to the skies over how in love she is with beau of six months Eric Johnson, she's apparently having a tough time dealing with her former hubby's plans to reclaim his newlywed status five years after their breakup.

"Even though Jessica wants to be happy for Nick, this is a very difficult time for her," a Simpson pal alleges to PopEater. "Nick was the love of her life then, man, and he was her first, so she will always have a very special place in her heart for him. She's deeply saddened."

Simpson, you'll recall, reportedly initiated their divorce after three years of MTV-documented marriage. Despite being entitled to half the starlet's fortune due to their lack of prenup, Nick is said to have settled for considerably less (still, Jess supposedly sniped during their recent restaurant run-in, "I hope Vanessa likes her clothes because I bought them for her, since Nick took all my money"). Lachey began dating Minnillo in 2006.

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"Nick knows what it's like to lose someone that you love and wasn't going to let it happen again," explains a Lachey confidant. "He never thought he would ever get married again after Jessica broke his heart. He never thought he would ever allow himself to be vulnerable again, but after dating for a long time he trusts Vanessa and knows she's the girl he wants to spend the rest of his life with."

According to People, Lachey got down on bended knee to slip an Asscher-cut sparkler on Minnillo's finger "near a beach" in California on Thursday, which sounds slightly less elaborate than the chartered yacht he rented in Hawaii for his sunset proposal to Simpson in 2002.

PopEater says Jessica hasn't yet called her ex to pass along her best wishes because she's worried it might ring false.

"If you can't say something nice," points out a source, "it's better to say nothing at all."

But another spy assures the Chicago Sun-Times, "Jessica is very happy for Nick, and only wishes him and Vanessa all the best."

We contacted Simpson's rep for an official statement on Lachey's engagement but were told, "There is no comment."

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