Hmm… there seem to be a lot more job openings at Kensington Palace these days. Earlier this month, Meghan Markle‘s assistant quit after just six months on the job, becoming the third member on her camp to resign. Now, a source tells In Touch magazine it’s because of the pregnant royal‘s “ludicrous demands.”

“It didn’t take long for Meghan to show her true colors once [Prince] Harry popped the question,” the insider told the publication. “She turned into a total bridezilla before the May wedding and made all kinds of ludicrous demands.”

One of those demands? Tiara-gate. According to a new biography about Prince Charles, Meghan, 37, reportedly clashed with the Queen over which headpiece she would wear on her big day. She apparently wanted a tiara with emeralds, like the one Princess Eugenie wore a few months later.

Meghan Markle tiara
WINDSOR, UNITED KINGDOM: Meghan, Duchess of Sussex, traveled in an Ascot Landau carriage as she and Prince Harry began their procession through Windsor following their wedding at St George’s Chapel. (Photo by Max Mumby/Indigo/Getty Images) Getty Images

“Meghan is a perfectionist and gets stressed if things don’t go her way,” the source added.

Still, while Harry feels like his wife needs to “calm down,” others say the former Suits actress simply has a strong work ethic. “Her heart is in the right place — she just wants to make a good impression and do good work,” the source explained. “Plus, it isn’t easy to juggle being pregnant with royal duties and adapting to a new life in a new country.”

But with all the pressure she’s faced since marrying into the family, “there are times when she feels exhausted and overwhelmed. And if things don’t go her way, everyone knows about it.”

Concluded the source, “There’s a fine line between determination and knowing your place. Unless Meghan changes her ways, it’s likely to only be a matter of time before everything blows up.”

For more on this story, pick up the latest issue of In Touch Weekly, on newsstands now!