Life comes at you fast.
In 2012, as Mitt Romney was on his way to winning the Republican nomination for president, he picked up a high-profile endorsement -- from Donald Trump.
Now, as Trump leads the pack of Republican candidates hoping to win the presidency in 2016, Romney has thoroughly denounced Trump -- who has denounced Romney right back.
Here's what Trump said about Romney in 2012
It's my honor, real honor, and privilege to endorse Mitt Romney.... Mitt is tough, he's smart, he's sharp. He's not going to allow bad things to continue to happen to this country that we all love. So, Gov. Romney? Go out and get 'em. You can do it.
Donald Trump at a Feb. 2, 2012, news conference at Trump's hotel in Las Vegas
Here's what Romney said about Trump in 2012
Being in Donald Trump's magnificent hotel, and having his endorsement, is a delight. I'm so honored and pleased to have his endorsement.... Donald Trump has shown an extraordinary ability to understand how our economy works, to create jobs for the American people.... It means a great deal to me to have the endorsement of Mr. Trump and people across this country who care about the future of America.
Mitt Romney, at the same 2012 news conference
Former Republican presidential candidate Mitt Romney weighs in on the Republican presidential race during a speech at the University of Utah in Salt Lake City on Thursday. (Rick Bowmer / Associated Press)
Here's what Romney says about Trump in 2016
If we Republicans choose Donald Trump as our nominee, the prospects for a safe and prosperous future are greatly diminished.... If Donald Trump’s plans were ever implemented, the country would sink into prolonged recession.... Donald Trump is a phony, a fraud. His promises are as worthless as a degree from Trump University.
Mitt Romney in a speech Thursday at the University of Utah in Salt Lake City
Here's what Trump says about Romney in 2016
He was begging for my endorsement. I could have said 'Mitt, drop to your knees,' and he would have dropped to his knees.... It was a horrible campaign... Mitt was a disaster as a candidate.... He's a choke artist.... Mitt did a big, big choke ... Mitt chickened out.... He doesn't have what it takes to be president.
Donald Trump's response in a speech in Portland, Maine, on Thursday
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