Guests were said to be moved to tears as Prince Charles and newly-married Prince Harry gave speeches at a lunchtime reception in Windsor Castle.
Harry was applauded as he referred to Meghan as his wife, just a short time after the couple were wed in St George's Chapel.
Guests heard how Harry and Meghan, who will now be known as the Duke and Duchess of Sussex, gel well together, said Suhani Jalota, founder of the India-based Myna Mahila charity.
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The 23-year-old described the speeches as "lovely".
"Some people were even crying. I think it was just a very, really nice atmosphere to be in where everybody felt really loved," she said.
"Essentially, it was just about how Harry was as a child and growing up. And now just about the couple and how beautiful they are together. So, I think it was just about their personalities and how they gel really well together."
She said people clapped when Harry described Meghan as his wife.
"He was talking about his wife and you know everybody was clapping because it was the first time he was using that term for Meghan, so it was really nice," she added.
Jalota said Elton John's performance was " incredible", although she was unsure which songs he performed.
"It became like a mini concert in the reception area. It was great," she said.
Asked how the couple were together at the reception, she said: "Lovely. They're just a beautiful couple together."
Meghan has been a strong supporter of the charity, which works with women in Indian slums to provide affordable feminine hygiene products.
"She really knows her stuff (about the cause). She's not in it just because it's trendy but really because it matters," Jalota said.
It is one of the charities chosen to benefit from donations in lieu of wedding gifts for the couple.
