I don't believe HM is abdicating due to rumors (brought about by gossip magazines) of marriage trouble in the Crown Prince marriage. Margrethe has had total knee replacement on both knees and that's the reason that she sits at receptions for the last several years.
The spinal surgery she underwent earlier this year was extensive, it lasted nearly eight hours, that's a lot for anyone at her age, I'm only speculating, she may have had a fusion at more that one level plus rod and screw insertions. Again, I'm only speculating. She's had to use a cane since then.
HM may have pondered over the late QE II's last years and then her brother-in-law, Costantine's last years and came to the decision it was time to pass the torch. We saw the preview with the change in titles of Joachim's children and discussed that the move was one that HM would make to take the burden off of the Crown Prince when he became Monarch. She would take the heat.
*Should have been "more than one level"
In regards to Frederik's affair, the one in question angrily denied the story and from the so-called photos published, I didn't see anything incriminating in them. Of course, I could be wrong, right now I don't see jumping to any definite conclusions.
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