Mrs. Trump, who was interviewed by ABC while touring Africa last week, said people are just spreading rumors about her marriage.
"I know people like to speculate and media like to speculate about our marriage and circulate the gossip," she said. "But I understand the gossip sells newspapers, magazines ... and, unfortunately, we live in this kind of world today."
She insisted allegations of her husband's infidelities are not a concern.
Trump, who during the 2016 presidential campaign was heard on an old "Access Hollywood" tape talking about groping and trying to have sex with women, has been accused of having multiple affairs. Porn star Stormy Daniels and ex-Playboy Playmate Karen McDougal have said they had sex with him years ago.
Trump has denied the trysts with Daniels and McDougal but has acknowledged reimbursing his lawyer for a $130,000 hush money payment to Daniels. Mrs. Trump has generally kept quiet on the subject.
Asked in the ABC interview if she loves her husband, Mrs. Trump said, "Yes, we are fine. Yes."
She played down a suggestion the repeated rumors of his philandering had put a strain on their marriage.
"It is not concern and focus of mine," she said. "I'm a mother and a first lady, and I have much more important things to think about and to do."
But when asked if the repeated rumors had hurt her, she paused. Then she reiterated the "media world is speculating."
"Yeah, it's not always pleasant, of course," she said. "But I know what is right and what is wrong and what is true and not true."
Portions of Mrs. Trump's interview aired Friday on "Good Morning America." ABC News aired more from the interview during an hourlong special broadcast Friday night, during which she explained why she wore a jacket that said "I really don't care, do u?" on a trip to the border to visit migrant children who had been separated from their parents.
She noted that she wore the jacket getting on and off the plane, but not during her visits with children, and said it was a message to "people and the left-wing media who are criticizing me."
Mrs. Trump said the jacket was a statement that the criticism will not stop her from doing "what I feel is right."
She said she purposely wore the jacket on the flight back to Washington after seeing "how the media was obsessed about it."
"It was kind of a message, yes," the first lady said.
In another portion of the interview, which aired earlier this week, Mrs. Trump says she could be "the most bullied person" in the world and women who make accusations of sexual assault need to "show the evidence."
Donald Trump, on the 2005 "Access Hollywood" tape that became public late in the 2016 campaign, says when he's attracted to beautiful women, "I just start kissing them. It's like a magnet." He said when you're a star, women let you.
"Grab them by the p----," Trump adds. "You can do anything."
Trump's former personal lawyer Michael Cohen pleaded guilty in August to campaign finance violations alleging he, Trump and the National Enquirer tabloid were involved in buying the silence of Daniels and McDougal after they alleged affairs with Trump.
AP Media Writer David Bauder in New York and Associated Press writer Darlene Superville in contributed to this report.
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