Despite claims the Duchess of Sussex was heavily involved in the writing of the book, this was not the case.
"Meghan can now see that, whether it’s fair or not, they are being viewed as these professional whiners and it’s not as simple as her distancing herself, because she has to be seen as fully supportive of Harry," insiders told Heat.
"She’s now regretting that she wasn’t more hands-on or involved when he was putting his book together," they added.
"This theory that she micromanaged what he wrote or had any say in the manuscript is totally wrong – it was Harry’s book and she let him get on with it. The same went for his interviews and promo tours – that was evidenced by the fact she let him do those by himself and made a point not to interfere."
Spare was released in January this year and went on to break records and become the fastest-selling non-fiction book.
Sussexes left 'devastated' by snub
It comes after the pair were allegedly left 'devastated' after being snubbed by the Primetime Emmys for their Netflix docuseries Harry & Meghan.
"But of course [the couple] will not show it," Ingrid Seward, royal expert and editor-in-chief of Majesty magazine, told The Mirror.
The docuseries was the first project to come from the Sussexes' deal with Netflix, with the next rumoured to be about his Invictus charity.
Harry & Meghan aired three months after the Queen's death in December, with the pair slammed over the way they spoke about the royal family.
"In the series, Harry and Meghan talk about the royal family as if they were the enemy, while they themselves are trying to save the world," Seward added.
While viewers seemed to love the series, which broke a Netflix record for the biggest documentary debut with 81.6 million views in the first four days, this "was obviously not good enough for an Emmy nomination".
The pair did receive a nomination for the Hollywood Critics Award in Best Streaming Nonfiction, with the royal expert saying, "Meghan and Harry will concentrate in this and make it a positive, however irritated they might be not to be in the Emmy nominations."
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