It looks like the honeymoon is over, and they’re not even married yet.  Nick Lachey and Vanessa Minnillo are reportedly heading for rough waters, and it’s resonating straight from the “What’s Left Of Me” singer’s past.

When Lachey and Jessica Simpson divorced, the damage was far-reaching.  And Nick won’t make the same mistake twice.

But Vanessa is furious that he wants a prenuptial agreement.  According to a source, “Vanessa has hit Nick with a wedding ultimatum – ‘Marry me by next year without a prenup or I’m gone!’”

Another source added, “Vanessa loves Nick, but she’s prepared to walk if he’s not willing to marry her.  And she’s not going to get involved in a prenuptial agreement. She feels marriage is forever, and she doesn’t want to begin a lifelong commitment by signing an agreement that’s just an out for a divorce.”

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