The Short Answer
No, Katy Tur was not married to Keith Olbermann. They worked together at MSNBC for several years, which is where the confusion started. People assume proximity means romance or marriage when it usually just means good editing schedules. Katy Tur is a journalist who worked as a correspondent and anchor for MSNBC. She's been married to David Thorpe, a sports commentator and author, since 2007. They have children together and live in Connecticut. Keith Olbermann was also at MSNBC during roughly the same period. He left in 2012. Their timelines overlapped significantly enough that rumors started floating around when they were both on screen frequently. That's about it. I remember reading forum threads in the early 2010s where people were connecting dots that weren't there. You'd see posts like "they looked at each other during the election coverage, that has to mean something." It didn't. They were colleagues. That's not dramatic, that's just how a newsroom works.
Here's what actually happened. Tur joined MSNBC in 2006. She was on various programs covering politics and breaking news. Olbermann had his own show, Countdown, which ran until he was let go in late 2012 over conduct issues that had nothing to do with Tur. They appeared on the same network. Sometimes the same shows. Not very often actually, but when cable news has two personalities with overlapping coverage areas, you see them together enough to create narrative patterns in people's heads. I dealt with this kind of situation a few times when I was fact-checking celebrity relationship rumors for a media blog back in 2015. The pattern is always the same: two people appear in the same professional context, internet users decide that's insufficient evidence and immediately fill in the blanks with speculation. I learned to stop engaging with those threads after the third one. Nothing you say will change the minds of people who've already decided the answer is yes. Tur herself has never addressed the Olbermann rumor directly that I can find. She's spoken about her marriage to Thorpe in interviews. She's discussed her career. She's been pretty open about her professional life in general. The silence on the Olbermann question was probably just because it was never a meaningful rumor worth responding to. You don't respond to everything someone says on the internet.
Their actual professional paths crossed in ways that might be interesting if you're studying cable news dynamics rather than gossip. Tur covered the 2016 election extensively and had some notable moments. Olbermann had already moved on to other projects by then. He was doing work elsewhere and later had some public controversies that made the rounds. None of it connects to Tur. If you want to verify any of this yourself, public records and interviews are straightforward. Thorpe has been photographed with Tur at events. They've been seen together publicly for years. Olbermann has been married twice himself to other people. The timeline doesn't support any connection beyond professional overlap. One thing I noticed when I looked into this more carefully: a lot of the rumor traffic seems to come from people conflating different MSNBC personalities. Tur worked with a lot of people on that network. Rachel Maddow, Chris Hayes, Stephanie Ruhle. The mental catalog gets mixed up. You think someone else and project that onto Tur.
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I wish more people would just check a basic bio before writing a 400-word theory. But I also know why they don't. The internet rewards engagement, and speculation gets more clicks than "these two people worked at the same place." That's just human nature. Not worth getting upset about.