It’s been a real balancing act for Kate Middleton and Prince William ever since Prince Harry and Meghan Markle split from the royal family and began living their new life as a family of three with son Archie overseas.

The Duchess of Cambridge’s schedule remains packed with charity events and personal appearances on behalf of the crown. It’ll likely become even busier in the coming weeks now that Harry, 35, and Meghan, 38, have moved to Canada and left their royal duties behind. “Kate’s disappointed in Harry and Meghan,” confides a friend exclusively to Closer Weekly in the magazine’s latest issue, on newsstands now. “She and William have been left to pick up the pieces and it’s causing a lot of stress.”

Carole Middleton and Kate Middleton

Unlike Meghan, Kate, also 38, had a full decade before she married William, 37, to decide if royal life suited her. She began dating William as a college student in 2001 and the couple split up twice before getting serious about marriage. “It’s not easy for anyone marrying into the royal family — you only have to look at Fergie [Sarah Ferguson], Meghan and even Princess Diana’s struggles,” says the friend. “Kate’s feeling overwhelmed at the moment, but that doesn’t mean she won’t cope. Her priority has always been to serve the queen.”

Since her 2011 marriage, Kate has become an expert at performing under pressure with grace, style and kindness. As she takes on more responsibilities — Kate recently kicked off a campaign to enhance early childhood development in the U.K. — she’s been forced to depend on others more in her private life. “Her mother is her No. 1 confidante,” says the friend, adding that Carole Middleton has been stepping in to help out with George, 6, Charlotte, 4, and Louis, 1. “They also have a nanny, of course.”

No matter how stressed she’s been, Kate’s tried to be there for William. Emotionally, her husband has had a very difficult time coming to terms with Harry’s departure. “Kate likes to keep the peace and isn’t a fan of conflict. She hopes that in time the brothers will reconcile,” says the friend, who adds that Harry and Meghan’s absence has been hard on Kate, too. “Kate loved Harry like a brother. She misses him.”

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