Transcript for Melania Trump: Alleged infidelities 'not concern and focus' of hers

The first lady speaking about her marriage to trump and allegations of infidelity. Tom llamas on the exclue and the scrutiny she has endured. Reporter: Through it all, she has held her tongue. Silent when porn star stormy Daniels stepped forward. Silent when the white house denied the affair. Silent when the president later admitted to paying hush money. But now, in our exclusive interview, first lady Melania trump is finally ready to talk. You did agree to this interview, to your credit, with no preconditions. Correct. Reporter: Knowing that there could be some -- some tough questions asked. It has been a tough year for you personally. You're not the first first lady to have to deal with her husband's alleged infidelities. Has this put a strain on your marriage? It is not concern and focus of mine. I'm a mother and a first lady, and I have much more important things to think about and to do. I know people like to speculate and media like to speculate about our marriage and circulate the gossip, but I understand the gossip sells newspapers, magazines, getting advertisers, and unfortunately, we live in this kind of world today. Reporter: Have you been hurt, though? Media, what they are speculating. Yeah. It's not always pleasant, of course. But I know what is right and what is wrong and what is true or not true. Reporter: Though the first lady insists she's not focused on the swirl of scandal, it's clear she is paying close attention. And she was not happy when her husband's lawyer seemed to put words in her mouth. She believes in her husband. She knows it's not true. I don't even think there's a slight suspicion that it's true. Reporter:the next day from the first lady's spokeswoman, I don't believe Mrs. Trump has ever discussed her thoughts on anything with Mr. Giuliani. The only time you have commented publicly, your office, was when Rudy Giuliani came out and said your thoughts about stormy Daniels' claims, and said, "She believes in her husband. She knows it's not true." Is that an accurate statement? I never talked to Mr. Giuliani. Reporter: Why do you think he came out and said that? I don't know. You need to ask him. Reporter: You mentioned you -- you still have a good marriage. Do you love your husband? Yes, we are fine. Yes. It's what media speculate, and it's gossip. It's not always correct stuff. Incredibly candid first lady and she was willing to answer questions able everything in the interview with you. I was struck earlier this week what she said about certain people in the administration. Didn't name names obviously. But there were people she couldn't trust in the white house. That's right and the president has responded to that. He said, we have great people. There are some I'm not in love with, yes, and we'll weed them out slowly but surely. One of the things we learned, when Melania trump doesn't like something, staff in the white house or the immigration policies, she lets her husband know. There is more to this. Tom, thanks to you and the wide ranges interview about the president, how she says she's been bullied. 10:00 P.M. Eastern, on a special "20/20." We'll see you then. In the meantime, outrage over pope Francis's comments on

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