That wait is almost over.
On Thursday, the self-described royal superfan and her mother Marie Evans stood in front of London's Buckingham Palace all set to travel to Windsor, where the wedding will be held on Saturday.
"When you have a hobby like knitting you often have something to show for it. With royals you get to go to the events," said Deaver, 27, who runs the Royal Tiara blog, which focuses on the history of such headgear. "Going to the wedding makes it real so it's not just me sitting on my computer looking at pictures."
Deaver and Evans, 59, aren't the only Americans to descend on Britain for Harry and Markle's big day.
A total of around d 100,000 visitors are expectedto be in Windsor — which usually has a population of around 31,000 — to celebrate and hopefully catch a glimpse of the couple. There are typically 88,000 Americans in the U.K. on any given May day, according to national tourism agency Visit Britain. Many of these will likely head to Windsor this weekend.
Deaver carefully planned out how she and her mother will spend Saturday. First, they'll catch a train no later than 6 a.m. to Windsor, which is some 25 miles west of London. Then they'll look for a big screen in a park to watch the ceremony. Next they'll try and secure a good spot along the route where Harry and Markle will take a post-wedding carriage ride.
During the rest of their week-long trip, Deaver and Evans will stop at other royal hot spots like Kensington Palace, where Princes Harry and William live, the Tower of London to see the Crown Jewels, and the hospital where Kate, the Duchess of Cambridge, recently delivered Prince Louis.
Mother and daughter are also stocking up on royal memorabilia.
"I've got my eye on tea towels, mugs, Christmas ornaments, and coloring books. I'm sure there will be lots of ridiculous things," said Deaver who had never heard of Markle until the former "Suits" star began dating Harry. Since then she's binge-watched the legal drama through its seventh season.
"The fact that she’s bi-racial, it’s just fantastic that the royal family is being open and accepting of that."
Deaver estimates the trip will cost between $3,000 and $4,000, including souvenirs.
Indeed, the royal wedding is big business for London shops, where retailers in the popular West End shopping district predict a windfall of around $80 million thanks to the nuptials.
Brooklyn-based Mexican-American stand-up comedian Veronica Garza has brought an extra bag to fit all the souvenirs she plans to buy. One thing on her list is a plate with Harry and Markle's faces to give to her mother — a fellow fan who gave her the royal bug when she was a child.
"I like Harry a lot. He's was just this unattractive little thing and he grew up to be hot. And he got Meghan Markle, who is beautiful. It's just very 2018 and progressive," said Garza, 34, who said she convinced her girlfriend, Leslie Knott, to make the big trip with her.
"I've always been a fan, because its something [Americans] don't have," she added. "But now, I'm invested, I'm part of this. We're here, we're going, it's like I have a stake in it."
Markle's background gave royal fan Elizabeth Mahon an extra push to fly over from New York.
Describing herself as multiracial, Mahon said she wanted to be in Windsor to witness a fellow multiracial woman marrying into Britain's royal family.
Harry and Markle's marriage gives little girls of color the chance to believe "they too can be a princess," said the 53-year-old author of "Scandalous Women," a book about history's most notorious women.
"The fact that she's biracial, it's just fantastic that the royal family is being open and accepting of that," said Mahon, who met with NBC News on Thursday outside Buckingham Palace along with other American fans of the royals. "That's the thing that to me is really so special, that she's so proud of being biracial."
There's an enduring fascination with the House of Windsor in the U.S., with the media covering their every move almost as closely as the British media.
Eager fans follow blogs about the ins and outs of royal private lives as well as what they wear.
Many royal watchers have formed a community around their fandom.
Deaver, the Texan visiting London with her mother, plans to meet up with friends she's made on Twitter while she's in England.
So does New Yorker Christina Jacob, 34, who became close friends with the creator of the "What Would Kate Do" blog after writing for it.
On Friday night, she hopes to celebrate atLondon's Madame Tussauds, which is displaying its new wax figures of Harry and Meghan.
Jacob has already bought a fascinator hat similar to the ones that British women often wear to weddings for her visit to Windsor.
"As a royal fan for so many years, being [in Windsor] with the crowds and everyone celebrating will be rewarding," she said.
Jenna Drenten, 33, has a more personal reason for flying out to the wedding from her home in Chicago.
Her sister Kristen, who passed away from cancer in 1997 at the age of 15, was a huge fan of William and Harry. She even had big posters of the two princes hanging in her bedroom.
Since her death, the whole family has followed the fortunes of the royal family as a way of remembering her.
"Going to Windsor is a tribute to my sister because the royals were something that she loved," said Drenten, who bought American flag headbands with big bows to wear in Windsor. "It's become something really sentimental to us all."