The former working royals are allegedly "living separate lives" and the Duke is thought to be "spending time in hotels".
Despite denials from sources close to Harry and Meghan, with one insider calling it "made up", one of Markle's ex-pals isn't convinced.
Some claim Harry has remained at the couple's home looking after their two children while Meghan "spends a lot of time" in Los Angeles.
But now, Lizzie Cundy – who met chum Meghan during a charity gala in 2013 – says the "writing is on the wall" for Prince Harry.
She told The Mirror: "I don't want to see any couples split up when any marriage falls apart it's sad, especially when you have children.
"We could all see the writing was on the wall, it's very different when you're a celebrity princess than being a royal princess and frankly Meghan just wasn't up for the job.
"She didn't want to put the hard work in opening hospitals and doing all the roles that royals do, it's not easy it's not glamorous, it's not like on the red carpet."
Cundy explained: "I think Meghan thought she was going to be the top dog star of the show and Princess Kate was always going to have that role."
On separation rumours, she said: "I think it will be in some respects better for Harry, we've got to look at it from Harry's side he's in California now, he's got none of his friends.
"He's got no family, he's got a rift with his father and his brother, it must be very lonely at times."
It comes amid a stressful time for the Duke and Duchess, the controversial release of Harry's book Spare, the Netflix hell and Meghan's lost Spotify dream.
On break-up whispers, a source close to the couple told Page Six: "It's not true, it's literally made up."
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