The former first minister announced she and Murrell would be ending their marriage after being separated “to all intents and purposes” for some time.
The news appeared on the front pages of almost every Scottish newspaper on Tuesday with Dugdale describing some of the coverage as “disgusting and awful” on Times Radio.
In the interview, Dugdale – who led Scottish Labour from 2015 to 2017 – was asked how sympathetic she felt towards Sturgeon following the announcement, to which she fiercely defended her former opponent.
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She said: “Deeply sympathetic and I will get a lot of crap on social media for saying that, and I say that as someone who was diametrically opposed to her for much of my political life.
“I stood up against her at First Minister’s Questions every week for about two and a half years.
“Yet, this is a deeply personal thing and for it to be played out on the front of every newspaper in Scotland this morning pretty much, and some of it is awful.
(Image: NQ) “Some of the coverage in some of the papers is disgusting and awful and very unkind.
“It’s a horrific thing for anyone to go through and anybody that has any compassion in their body can surely see that regardless of politics.”
Sturgeon and Murrell first became a couple in 2003, announcing their engagement seven years later, in January 2010.
The pair married at a ceremony in Glasgow’s Oran Mor in July 2010, while Sturgeon was health secretary and deputy first minister. She was 39 and he 45.
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It was confirmed at the time that Sturgeon would “100%” be keeping the name with which she had became notable in public life, with an SNP spokesperson saying she did not wish to “become the artist formerly known as”.
Sturgeon would go on to become SNP leader and first minister after the independence referendum of 2014 and Alex Salmond’s subsequent resignation.
During her nearly nine years in power, Sturgeon and Murrell would become known as the most powerful partnership in Scottish politics.
But in a post headed “personal” on Monday, Sturgeon wrote: “With a heavy heart I am confirming that Peter and I have decided to end our marriage.
“To all intents and purposes we have been separated for some time now and feel it is time to bring others up to speed with where we are.
“It goes without saying that we still care deeply for each other, and always will.
“We will be making no further comment.”
The news of the split comes after Murrell was charged in connection with embezzlement amid an ongoing police investigation into the SNP’s finances, dubbed Operation Branchform.
Murrell, who was the SNP’s chief executive from 2001 to 2023, was charged by police in April 2024.
Sturgeon has also been arrested and questioned by police investigation the SNP, but was released without charge in June 2023.
In December, Sturgeon said she knows “nothing more” about the investigation than she did when arrested.